Resin-bonded sand is widely used in China due to its production adaptability, great reclamation rate of used sand, good surface quality and dimensional accuracy of castings. This paper introduced the development history, application status and prospect of the three resin-bonded sand processes in China, including three kinds of no-bake resin-bonded sand(furan, alkaline phenolic and phenol urethane), hot core box and phenolic urethane cold box process. Possible ways were proposed aiming at the environmental problems in the application of the resin-bonded sand. It is pointed out that the application of the current resin-bonded sand technology will not change when the performance of inorganic binder sand cannot reach the level of the resin-bonded sand. Resin sand molding and core making are mainly made by cold method in order to save energy, better working conditions and to improve the accuracy of the sand cores. The combination of green,digitization and intelligentization makes the application of the resin-bonded sand technology to a new level.

This paper introduces the main revision contents of GB/T 2100—2017 standard, the brand, chemical composition, mechanical properties, heat treatment, welding repair, test methods and acceptance rules of general corrosion resistant steel castings, and the characteristics, typical application cases of the standard.The standard covers 27 kinds of stainless steel castings in three categories: martensite, austenite and duplex（austenite-ferrite）, which can meet the requirements of corrosion resistance and mechanical properties of castings in various corrosive working conditions. When selecting materials, it is necessary to combine the characteristics of stainless steel and the service environment, and comprehensively consider the material cost, manufacturing cost and process difficulty degree, so as to optimize the brand of corrosion resistant steel castings with high price-performance ratio, which improve the safety and reliability of equipment.

Tungsten-based alloys are the second largest category of tungsten-based products after cemented carbide, and their unique physical and mechanical properties make them useful in the defense industry and various areas of the national economy, but as future manufacturing industries require increasingly precise parts and more complex component designs, these requirements are difficult to achieve using traditional powder metallurgy method. Additive manufacturing（AM） offers unique geometric design freedom and rapid prototyping capabilities. This paper introduces the research progress of additive manufacturing tungsten-based alloys at home and abroad, and analyzes and outlooks the main problems and research trends facing the research.

The effects of pouring temperature and mold temperature on the solidification microstructure and mechanical properties of AlSi9Cu3 alloy were studied by direct reading spectrometer, metallographic microscope, tensile testing machine, JMatPro software, scanning electron microscope and X-ray diffractometer. The results showed that the solidification microstructure of the alloy was primary α-Al and acicular eutectic silicon. As the temperature of pouring decreased, the grain size of α-Al first decreased and then increased. The content of acicular eutectic silicon gradually increased. The tensile strength of the alloy first increased and then decreased. With the temperature of the mold temperature increased, the grain size of the α-Al increased gradually, the content of the acicular eutectic silicon decreased first and then increased. The mechanical properties of the AlSi9Cu3 alloy were the best when the pouring temperature was 680 ℃ and the mold temperature was 100 ℃.

With the rapid development of high-end equipment manufacturing industry, many new technologies, processes and equipment have been applied to the field of steel casting in China. Due to major breakthroughs in basic theoretical research and key preparation technologies, the microstructure, performance and casting quality of the large steel castings have been significantly improved. This paper focused on the development status and trend of the steel casting technology, such as the smelting and purification technology of the cast steel, new cast alloy steel, progress in numerical simulation of the cast steel, digital management system of integrated manufacturing of foundry enterprises, new technology of the special cast steel production, quality inspection of the cast steel, and key forming technology of the 100-ton large steel castings. The development direction of the steel casting technology is prospected.

This paper introduced the history and main contents of the standard, the main technical differences with the previous version of the standard and the application of the standard. It is scientific and practical to use mathematical statistics to verify and analyze the measured data in the process of standard revision. Since Mass Tolerances of Castings is related to dimensional casting tolerances, this standard supports the use of GB/T 6414-2017 "Castings-Dimensional Tolerances and Geometrical Tolerances and Machining Allowances".

Based on the casting forming of large complex thin-walled JG4247 alloy turbine rear casing, the shrinkage porosity and hot tearing tendency of the casing were comparatively simulated and analyzed by ProCAST software under different casting systems conditions. The results showed that compared with the top gating system, the riser and sprue realized the feeding of the multiple variable cross-section hot spots of the casing during the solidification process simultaneously by using the bottom gating system, which was a suitable casting system design for the turbine rear casing. Although the hot tearing tendency of the bottom gating system casing was slightly greater than that of the top gating system. While the further research revealed that the hot tearing tendency of the casing decreased with the reducing of pouring temperature or the increase of shell temperature under the condition of the bottom gating system, the latter factor played an important role in the system. Therefore, the hot tearing tendency of the casting with the condition of the bottom gating system could be reduced by increasing the shell temperature under the bottom gating system, and finally the high metallurgical quality JG4247 alloy turbine rear casing casting without crack and macro shrinkage inside could be obtained. The simulation results were consistent well with the actual casting results of the casing.

A comparative study on the microstructure and thickness of AISI 431 steel deposited by high-speed laser cladding using Gas Atomization(GA) and Supreme-speed Plasma-rotating Electrode Process(SS-PREP)powders has been carried out. Moreover, powder size, powder morphology and powder sphericity were analyzed. The influence of different powder sphericity on the quality of the high-speed cladding layer was compared. The result showed the sphericity and velocity of the powder produced by the SS-PREP method were better than those of the GA. Compared to the AISI 431 steel layer with GA powder, the deposition formed by the SS-PREP powder had finer dendrite structure and more uniform thickness. In general, the powder sphericity directly affects the quality of the high-speed cladding layer.

The research progress of four kinds of task solutions based on X-ray images of casting defect location detection, classification recognition, integration of detection and classification, and defect image simulation generation were reviewed. The existing methods of intelligent defect detection and recognition were compared, and the future research directions were prospected.

In the interests of pursuing the development of new high-performance cast alloys,the relationship between Cu,Mg element content and θ-Al₂Cu,Q phase content and formation temperature,the equilibrium phase diagram of Al-9Si-2Cu-xMg alloy and the variation curves of precipitated strengthening phase content with temperature and time were established by thermodynamic calculation of materials.Combined with DSC thermal analysis experiment,the alloy composition and heat treatment process of the Al-Si-Cu-Mg alloy were designed.The results showed that it was accurate and efficient to design the composition and heat treatment process of the Al-Si-Cu-Mg alloy by thermodynamic calculation of the materials,which improved the efficiency and reduced the cost of developing new alloys.The composition satisfied the relationship:9.5≤Cu+20.4Mg≤10.7,and 1.5%≤Cu≤2.5%,and 0.35%≤Mg≤0.45%.The heat treatment process was 500℃×3 h+530℃×9 hWQ+155℃×12 h.Average ultimate tensile strength at room temperature was 401 MPa,yield strength was 302 MPa,and the elongation was 5.3%,which reached-the performance level of high performance cast aluminum alloy.

The iron Buddha in Fuzhou Kaiyuan Temple （Kaiyuan iron Buddha） is one of the biggest ancient ones existing at home and abroad.X-ray photoelectron spectroscopy （XPS） technique was used to characterize the near surface and near core regions of the iron Buddha.The fitting analysis of the Fe 2p and C 1s spectra quantitatively identified the existence of α-Fe,Fe₃C,graphite,α-Fe₂O₃ and Si C.The results showed that the corrosion product on the surface of the iron Buddha was α-Fe₂O₃,and the near surface and core regions of the iron Buddha exhibited the structures of white and mottled cast irons,respectively,and the Si C was brought from polishing agent.The respective graphite conversion rate R,of the cementite was obtained by calculation,being 5.45 mol%and 21.7 mol%,respectively.The authors discussed the characteristics and forming mechanism of the metallographic microstructure of the iron Buddha,unraveled the reason of the exceptional corrosion resistance,and summarized the advantages of quantitative analysis of the XPS on cast irons in particular the historical iron relic.The analysis approach in this paper is expected to be a useful reference in the research community.

The liquid metal fluidity test experiment is a very important large-scale comprehensive experiment for the major of materials forming and control engineering(casting direction).Fluidity is a very important casting performance index of the liquid metal.The spiral fluidity experiment is a common experimental method to determine the fluidity of the liquid metal in sand molds.The concentric triple spiral fluidity sample molding template is the most important tooling for the spiral fluidity experiment method.In this paper, according to the structural characteristics of the molding template casting, a preliminary casting process scheme was designed and then was optimized with the ProCAST numerical simulation software.Subsequently, based on the optimized casting process scheme, a concentric triple spiral fluidity sample molding template casting product was actually produced by using the digital pattern-less casting precision forming technology.Finally, with the molding template casting produced, the experimental course of the liquid metal fluidity test was conducted for the undergraduates majored in the materials forming and control engineering in our university, and a good experimental teaching effect was achieved.

This study introduced that the casting process design plan of a high-end CNC lathe obliqued-guide bed casting from the determination of process parameters such as pouring position, parting surface, machining allowance and parting negative number, to core design, pouring system design, exhaust riser design, core sand ratio,smelting plan, etc. Aiming at the blowhole defects of the castings, specific analysis was carried out from the porosity formation mechanism, process design scheme, on-site operation, performance status of the pouring process and so on. After production verification, the blowholes problem of the castings has been effectively solved by improving the design of the sand core, setting the exhaust channel reasonably, and standardizing the actual operation.

The aluminum alloy chassis structure parts were produced by gravity tilting casting process. The chassis structure part is a subframe bracket for a luxury European brand chassis, the material is ALSi7Mg0.3, and the weight is about 3 kg. The size range is 330 mm×260 mm×250 mm. The minimum wall thickness is 5 mm, and the maximum wall thickness is 36 mm. The overall structure of the product in the shape of ‘L’. By adopting gravity tilting casting process, hydrogenation refining process and T6 heat treatment process, the subframe brackets could reach the performance requirements of yield strength R_p0.2≥190 MPa, tensile strength R_m≥230 MPa, elongation A_{(50 mm)}≥ 3 % and hardness HBW80-110.

The steel plate stamping and welding seat back of a certain model was taken as the research object. Through lightweight design, the development of magnesium alloy seat back with integrated structure as the core was realized, and the trial production of the casting was completed by high-pressure casting process, and the weight reduction effect of the product reached 49.6%. The structural design, simulation and collision test showed that the magnesium alloy seat back can meet the use needs of the seat, greatly reduce the weight and generation cost, and meet the needs of vehicle lightweight.

Through the analysis of the structural characteristics of large die-casting die, this paper put forward the optimization scheme of die insert structure, guide structure, shunting cone, molten cup and core pulling cylinder. Through practice, it is verified that it not only improved the quality, maintainability and finished product rate of die-casting, but also reduced the processing difficulty of die, and improved the production efficiency and die life.

The effects of heat treatment on the mechanical properties and thermal conductivity of die cast ZL102aluminum alloy were studied by microstructure characterization and mechanical/thermal performance testing. The results showed that the phases in the microstructure of die cast ZL102 aluminum alloy at room temperature included primary α(Al), Al-Si eutectic, primary silicon and a small amount of intermetallic compounds. The silicon phase in the die cast ZL102 aluminum alloy was fused and spheroidized after solution treatment. During aging treatment, granular second phases precipitated in α(Al) matrix, and the sphericity of the silicon phase at grain boundaries was further improved. Under the three heat treatment conditions, the mechanical properties of the ZL102 aluminum alloy after solution treatment were the highest, but the thermal conductivity was the lowest. Generally, the aging treatment can ensure the alloy a good combination of the mechanical properties and thermal conductivity, i.e., the ultimate tensile strength of the alloy was 212 MPa,the elongation was 3.9%, and the thermal conductivity at room temperature was 142.7 W/(m·K).

The outer layer of a centrifugal casting compound high speed roll was formed by horizontal centrifugal casting and the core part was obtained by gravity casting. Shrinkage porosity was found in the upper and lower of the roller body in finished product. The temperature field changes, Niyama criterion, shrinkage porosity and shrinkage cavity during the stages of the horizontal centrifugal casting process for the outer-layer and the gravity casting process for the core part were calculated by using of numerical simulation method,and the effects of chief processing parameters on the whole mold filling and solidification processes were analyzed. The results showed that the solidifying sequence of the outer-layer longitudinal section was from the both ends to the middle, and that of the outer-layer cross-section was from the outer layer to the inner layer, and the increase of rotational rate might reduce the solidification time of the outer-layer; the shrinkage porosities and holes easily occurred in the upper and lower roll body and the center of the roll core. Highquality compound high speed roll can be obtained through increasing pouring rate of the gravity casting with sequential solidification from bottom to top. Finally, actual production verifications have been carried out.

The wear resistance of hypereutectic high chromium cast iron was improved by metal mold casting before and after Ce modification.By means of OM,SEM,XRD,hardness tester and wear testing machine,the microstructure and properties of hypereutectic high chromium cast iron before and after Ce modification were studied.The results show that the microstructure of hypereutectic high chromium cast iron before and after modification is composed of primary M₇C₃+eutectic M₇C₃+austenite+martensite.Compared with the pre-modification M₇C₃,the morphology of the primary M₇C₃ transformed from a long hexagon to a rounded hexagon,the size decreased by 44.9%,and the volume fraction increased by 30.2%.The Rockwell hardness,impact toughness and bending strength of cast iron are increased by 5.0%,43.4%and 39.2%respectively,and the weight loss is reduced by 50.7%.The compound Ce₂O₂S of Ce is moderately effective as the heterogeneous nucleation core of M₇C₃,and Ce can spherodize and purify the inclusions.The refined primary carbides protect each other with the matrix,which improves the surface wear resistance of cast iron.The wear mechanism of the cast iron is changed from micro-cutting mainly and fracture shedding as auxiliary.

A whole set of casting process of pure titanium impeller was designed with the considering of material property, the structure and technical requirements, and a sample casting was produced. The process defects were reproduced and optimized by ProCAST finite element analysis software, the method of casting defect control was improved, the casting forming problem was solved, and finally the high-precision and high-quality pure titanium impeller casting was produced.

The calculated phase diagrams of Al-17%Si alloy with the addition of Mg up to 10 wt.% indicate two critical composition points at 4.6 wt.% and 6.8 wt.% Mg where the liquidus and binary reaction temperatures as well as the temperature range of the Mg₂ Si phase formation have been changed. The eutectic formation temperature is decreased with the addition of Mg up to 4.6 wt.% Mg, followed by constant value due to the change of the eutectic formation reaction from the binary(L→Al+Si) to the ternary(L→Al+Si+Mg₂ Si). This change contributes to the transformation of the eutectic silicon in matrix from long platelet to short rod particles, resulting in overall increased hardness of the high Mg alloys even though the hardness of the primary Mg₂ Si particles is much smaller than that of the primary silicon particles.

The repairing of the fluorescence indication defects takes a long time in the production process of superalloy investment castings, which is one of the main factors affecting the quality and schedule of the castings. The K536 superalloy investment castings were made by cold crucible vacuum levitation melting equipment and vacuum induction melting and casting equipment, respectively, and the chemical composition analysis, the X-ray inspection and the fluorescence penetrant testing were carried out on these castings. The results showed that the castings obtained by the cold crucible vacuum levitation melting equipment had almost no fluorescent indication defects, but the castings manufactured by the vacuum induction melting and casting equipment had dense fluorescent display defects. It is proved applying the cold crucible vacuum levitation melting technology can reduce the fluorescent indication defects of the superalloy investment casting and post-treatment workload.

His paper summarizes the research progress of selective laser melting（SLM） technology of nickel base superalloy, mainly expounds the changes of typical solidification microstructure and properties in the deposited state, the influence of process parameters on the results of additive manufacturing process of laser,the change of microstructure after heat treatment and its influence on mechanical properties, and summarizes the existing researches that it is difficult to reduce residual stress, control anisotropy.The research on selective laser melting of nickel base superalloys is prospected, which provides a useful reference for the development of selective laser melting technology of nickel base superalloys.

A 50 kg vacuum induction furnace was used to smelt C-HRA-3 nickel base heat resistant alloy. The effects of refining time on the change of oxygen content and the characteristics of non-metallic inclusions, such as quantity, size and type, were studied. The results showed that at the initial stage of the refining within 0-90min, the content of [O] in liquid alloy decreased with the extension of the refining time. However, at a certain time from 90 min to 120 min of the refining period, the decomposition reaction rate of MgO crucible was greater than that of carbon deoxidation, which led to the secondary increase of the [O] content. The limiting link of carbon the deoxidation reaction in vacuum smelting of the C-HRA-3 alloy was the mass transfer of the [O] into the reaction interface in the liquid phase boundary layer. Combined with the experimental results,the average mass transfer coefficient of the [O] was calculated to be 2.68×10-3 cm/s. Under the influence of electromagnetic stirring in vacuum induction furnace, as the refining time reached 90 min, the number and size of non-metallic inclusions in the alloy were minimum. The inclusions in the C-HRA-3 alloy were mainly alumina and magnesia alumina spinel.

With the increasing need for lightweight piston, the wall thickness of window and combustion chamber are becoming thinner and thinner.In the process of piston casting, the casting defects such as confluence line and cold shut become particularly prominent. In order to eliminate these defects, inert gas protection technology was used, which improved effectively the filling ability of aluminum alloy melt, and the casting defects thereby were reduced. In the mass production, the casting scrap rate decreased from the highest 4.70% to 0.18%.

In order to improve the comprehensive performance of silicon-based ceramic core, zirconia fibers with different contents were added to the core matrix powder with zirconia powder as mineralizing agent, and silicon oxide ceramic cores were prepared by hot pressure injection method. The variations of the core shrinkage, porosity and mechanical properties with different zirconia fiber incorporation amounts were studied, and the micro morphologies of the sample sections were observed. The results showed that when the zirconia fiber incorporation increased from 0 to 5%, the room temperature and high temperature flexural strength at 1 550 ℃ of the ceramic core specimens first increased and then decreased. When the zirconia fiber incorporation amount was 1%, the bending strength at room temperature and at 1 550 ℃ was the best,which were 18.64 MPa and 28.06 MPa, respectively, which increased by 15.84% and 13.46% compared with unfiber-reinforced ceramic core samples. The shrinkage rate of the ceramic core specimen with zirconia fiber incorporation amount of 1% was 0.89%, the apparent porosity was 30.4%, and the high temperature deformation was 0.71 mm. It is concluded that the high amount of the zirconia fiber content led to the destruction of fiber integrity and agglomeration, and the cutting effect on the matrix, which is the main reason for the deterioration of the comprehensive performance of the ceramic core samples.

In this paper, the leaf spring seat of ductile iron with high strength and toughness in as-cast condition was studied. After analyzing its three-dimensional structure and the solidification characteristics of hypereutectic ductile iron, the shape, size and position of riser were determined according to the modulus method, and two pouring systems of step type and top type were designed. The two kinds of casting processes were simulated by ProCAST software, and the simulation results were compared. Finally, the castings obtained under the step gating system were sampled and analyzed, and the mechanical properties, microstructure and fracture morphology of the five bulk samples were studied and compared.

金属锻錾是一门古来有之、经久不衰的手艺，是中国传统艺术及技艺领域的重要组成部分。顾名思义，所谓锻即“锻造”，泛指对金属材料的粗加工处理，目的是完成金属装饰的大致形态。所谓錾即“錾刻”，泛指利用錾刀在金属材料上精雕细琢，直到装饰效果完全实现。以绘画艺术形式类比，“锻和錾”是一体化的，前者类似于描边、后者类似于赋彩，两者结合才能完成金属浮雕装饰。故而，广义上金属锻錾是指以黄金、白银、青铜等为媒介，进而实现金属装饰设计、加工、制造的全部工艺过程。利用金属装饰锻錾工艺创作的艺术品类甚广，大到广场雕塑、建筑壁挂，小到器皿摆件、耳环项链，且艺术风格多元化、适用场景多，是一项具有重要传承与弘扬价值的工艺形式。

Heat treatment is an important method to improve the mechanical properties of Al-Si cast alloys.The research progress in heat treatment process of Al-Si cast alloys was expounded based on the investigations at home and abroad, focusing on the strengthening mechanism, microstructure, aging precipitation sequence of precipitates and the effects on mechanical properties, and provided a reference for subsequent research and development.It is found that the changes occurring during solution treatment have been relatively well understood, and the equilibrium phase diagram can be used to predict the stability of phases at the solution treatment temperature.The influence of quench rate on subsequent artificial ageing needs to be studied further.

迈格码铸造模拟软件的最新版本MAGMASOFT^®6.0将给用户带来全新的体验。由于特别注重易用性和效率，用户将能更快速的达到其目标。MAGMASOFT^®6.0中直观的用户界面使用户能够更加精确的分析模拟结果并做出决策。MAGMASOFT^®6.0的操作更加简单和高效，将给客户提供全新的铸造工艺模拟的体验。

This article mainly analyzes the characteristics of the connection nodes of transmission towers, and analyzes the structural characteristics, technical requirements, heat treatment, welding and galvanizing processes of the cast steel joints used in the transmission tower combined with two cases. Engineering construction problems such as large welding volume were solved, high difficulty, and stress concentration in complex parts, and the construction cycle of transmission towers was shortened. Finally, the quality control measures for the production of cast steel joints of transmission tower are given.

To deal with the defects such as isolated liquid phase, hot spot and dispersed shrinkage in low-pressure casting of electric vehicle subframe caused by compact structure, non-uniform wall thickness, complex shape of spiral sand core and large volume proportion of sand core, AnyCasting software was used to simulate and analyze the influences of temperature, pressure and mold structure on solidification and crystallization quality of the low-pressure casting of sub frame. The occurrence of isolated liquid phase, hot spot and dispersed shrinkage of castings can be predicted by comprehensive numerical simulation with combined defect and probabilistic defect prediction function. Study the intelligent control method of AnyCasting in low-pressure casting mold cooling, and explore how to adjust the cooling solidification sequence of aluminum alloy by using the opening and closing sequence of cooling water pipes, so as to improve the internal structure and molding density of the subframe castings and the production quality of the low-pressure casting.

The effect of heat treatment including solution and aging treatment on the microstructure and mechanical properties of Tip/AZ91D composite(with 4.0vol%of metal Ti particles and average diameter of 6.5（m）fabricated by stir casting had been investigated by optical microscopy,scanning electron microscopy,X-ray diffraction,and microhardness and room temperature tensile mechanical properties tests.The results indicated that the solution treatment time of the Ti_p-AZ91D composite was 2 h,which was 8 h shorter than that of the AZ91D alloy.It was found that the eutectic phase size of β-Mg₁₇Al₁₂ in the composite was finer than that in the AZ91D alloy,which led to the rapidly dissolution.When aging at 168℃,the peak aging time of the composite was 16 h,which was half that of the AZ91D alloy.It was observed that the β phase precipitates at the Ti particles interface,which resulted in the rapidly age hardening.The yield and tensile strength of the composite was 150 MPa and 217 MPa,respectively,after aging treatment,both of which were increased compared with the matrix alloy.

The geometric structure and elastic properties of La and Ce doped α-Al were calculated from atomic scale by the first-principles plane-wave pseudo-potential method based on the density functional theory. The work will provide theoretical basis for the development of cast Al-RE alloys. The results show that La and Ce doping can change the structural parameters of α-Al, the binding energy of Al-Ce solid solution is lower than that of Al-La solid solution, the structural stability of Al-Ce solid solution is relatively high; the elastic properties analysis shows that La and Ce doping reduces the modulus of elasticity of α-Al, weakens the deformation resistance and reduces the symmetry of α-Al, and the doping system of Al-La/Ce solid solution is anisotropy, especially La doping α-Al. The analysis results of density of states show that the doping of La and Ce will increase the density of states near the Fermi level which is not zero and makes the system show certain metal properties, resulting in the decrease of strength and hardness, and the improvement of plasticity and toughness.

M₇C₃ carbide in high chrome cast iron makes it have excellent wear and corrosion resistance. Directional solidification technology can realize the directional arrangement of carbide. The hardness and wear resistance of high chromium cast iron with specific carbide orientation are different from ordinary high chromium cast iron. This paper introduces the development and characteristics of high-chromium cast iron and describes the characteristics of directional solidification technology. On this basis, the research progress of the hard phase directional solidification of cast wear-resistant alloys is summarized, and the future research direction of directional solidification technology in high chromium cast iron is given.

The article introduced the optimizing process of the riser which set on the center plate of ZK6 bolster. By analyzing the main problems of the original casting process using four blind risers, the casting process was optimized by using two open riser. It is verified that the quality of the castings after optimized has been significantly improved, which further provides a technical guarantee for the safe operation of the railway.

The application of ultra-high purity pig iron to the production of high-quality cast iron was discussed,including the productions of high-quality ductile iron, vermicular graphite cast iron and ADI castings. The high quality ductile iron requires very low chemical components such as Cr, V, Mo and As that affect the microstructure, so as to reduce the formation of pearlite and bad carbides. The high-quality ductile iron produced by the ultra-high purity pig iron cannot observe the obvious grain boundary flake graphite and pearlite structure under the ordinary microscope, so as to ensure the good mechanical properties of the material at low temperature. The high quality vermicular graphite cast iron produced by the ultra-high purity pig iron can greatly improve the fatigue strength and machinability of the vermicular graphite cast iron. The high quality austempered ductile iron(ADI) produced by the ultra-high purity pig iron can ensure high fatigue strength of the material.

The effects of components, properties, forming and removal process of common titanium alloy precision casting investment mold materials, such as photosensitive resin(SLA), polymer, wax based and resin based mold materials on investment mold quality and ash residue are systematically described. The future research and development of mold materials and demoulding process are prospected. It will provide a useful reference for the development of titanium alloy precision casting.