20 March 2021, Volume 45 Issue 3
    

  • Select all
    |
  • Research Progress on Influence of Applied Electromagnetic Field on Tribological Properties of Metal Material Friction Pair
    XIONG Zhen, XU Chunxia, HU Rui, XIONG Le, MAITI Raman, MCQUADE Catherine
    Materials For Mechanical Engineering. 2021, 45(3): 1-5,51. https://doi.org/10.11973/jxgccl202103001
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Applying an external electromagnetic field is one of the ways to improve the tribological performance of the friction pair. From three aspects of the promotion of dislocation movement, the enhancement of the oxidation of the contact surface and the refinement and oxidation of the wear debris by the external electromagnetic field, the mechanism of the electromagnetic field improving the tribological performance of the metal material friction pair is reviewed. The influence of the external electromagnetic field type, the magnetic field strength, the magnetic field application direction, the magnetic field frequency, the magnitude and difference of magnetic permeability of the friction pair material and the size of the external magnetic particle on the friction and wear of the friction pair is discribed. The future research direction on the anti-friction of the electromagnetic field is pointed out.
  • Effect of AlN Content on Microstructure and Properties ofTi(C,N)-Based Cermet
    WANG Chaofeng, CHEN Yikun, LIU Huachen, DU Xueming, YAO Zhenhua
    Materials For Mechanical Engineering. 2021, 45(3): 6-10. https://doi.org/10.11973/jxgccl202103002
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The effect of AlN addition amount (0,1%,2%,3%, mass fraction) on the hardness, bending strength and oxidation resistance of Ti(C,N)-based cermets was studied. The results show that the cermets with different addition amount of AlN were all mainly composed of Ti(C,N), Ni3Al and nickel phases. With increasing the addition amount of AlN, the hardness of the cermet increased, and the bending strength increased first and then decreased, reaching the peak value with 2%AlN. The oxidation mass gain of the cermet with 2%AlN increased slowly compared with the without AlN, and the oxide film structure was relatively dense, indicating the better oxidation resistance.
  • Amount of Wear Particles on Surface of Soft Styrene Butadiene Rubber Wheel and Wear Mechanism Under Different Working Conditions
    JIAO Runnan, HUANG Haibo, LI Jinbang, PAN Luqi, DONG Jianan
    Materials For Mechanical Engineering. 2021, 45(3): 11-15. https://doi.org/10.11973/jxgccl202103003
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The effects of wear time, load, rolling speed, and relative humidity on the number of wear particles on surface of soft styrene-butadiene rubber wheel and the rubber wheel temperature were studied with a self-designed friction and wear testing machine. The wear mechanism under different working conditions was analyzed. The influence degree of each factor was analyzed by orthogonal experiment. The results show that the number of wear particles increased with the increase of wear time and load, and decreased with the increase of rolling speed and relative humidity. The number of wear particles with particle size of 2.5 μm and the temperature of the rubber wheel had the same changing trend with various factors. The amount of the small wear particles could be predicted by temperature changes. The wear mode was fatigue wear under low load, and was fatigue wear and abrasive wear under high load. The order of the influence degree of each factor was load, rolling speed, relative humidity, type of grinding wheel. When the load was 100 N, the rolling speed was 8 m·s-1, the relative humidity was 60% and the grinding wheel was a cement wheel, the number of wear particles was the least.
  • Low Cycle Fatigue Properties of Nickel Base Single Crystal Superalloy at Different Temperatures
    SHI Zhenxue, HU Yingtao, LIU Shizhong
    Materials For Mechanical Engineering. 2021, 45(3): 16-20,28. https://doi.org/10.11973/jxgccl202103004
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The low cycle fatigue properties of the Ni-Cr-Co-Mo-W-Ta-Nb-Re-Al-Hf-C series single crystal superalloy at different temperatures (800, 980℃) were studied. The results show that compared with those at 800℃, the plastic deformation of the alloy at 980℃ was greater, the damage was more serious, the fatigue strength was lower, and the life was shorter. The fatigue fractures of the alloys at two temperatures were cleavage-like fractures. At 800℃, the crack initiated at the loose microstructure and propagated along the {111} plane, and the instantaneous fracture area was relatively large. At 980℃, the crack initiated at the brittle oxide scale and propagated along the {001} plane perpendicular to the stress axis, and the instantaneous fracture area was relatively small.
  • Effects of Zn Content in Filler and Welding Temperature onProperties of Joint of SiC/Al Composite
    LU Baoshan, LI Youzhi, GUAN Jiju
    Materials For Mechanical Engineering. 2021, 45(3): 21-28. https://doi.org/10.11973/jxgccl202103005
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Al/SiC composites were prepared by sintering aluminum powder and silicon carbide particles. The diffusion welding was conducted on the composite with fillers of Al-20SiC (mass fraction/%), Al-20SiC-20Zn, and Al-20SiC-40Zn as interlayer materials at 420,520,600℃, and the effects of Zn content in filler and welding temperature on the properties of joint of the composite were studied. The results show that the Zn near the joint was obviously agglomerated after welding at 420℃, and was not agglomerated after welding at 520, 600℃, indicating relatively high welding temperature contributed to uniform diffusion of Zn. The oxidation occurred at the joint after welding at 520℃ with Al-20SiC-40Zn filler, resulting in the obvious cracks at joint. The shear strength of the samples after welding with Al-20SiC-20Zn filler was bigger than that with Al-20SiC and Al-20SiC-40Zn fillers, and increased with increasing welding temperature. With increasing Zn content in the filler, the hardness of the joint increased, and was higher than that of the base metal. The hardness of the joint increased with increasing welding temperature, but the increase amplitude decreased.
  • Microstructure and Properties of Cast Iron Dryer after Long Term Service
    LIU Kexiu, MA Kuo, FENG Xiaoliang, WANG Lian, XIE Xiaowu, LU Zhongming, LI Lushui
    Materials For Mechanical Engineering. 2021, 45(3): 29-34. https://doi.org/10.11973/jxgccl202103006
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The microstructure and mechanical properties at different positions of the two cast iron dryers in a paper mill after service for 62 a and 43 a were studied. The results show that there was no obvious surface defects and crack defects on the cylinder and end cover of the two dryers. The microstructure of substrate was pearlite without obvious spheroidization, and the size and distribution of the graphite sheets were mainly A type. The length of the graphite sheet of the front end cover of the dryer after service for 62 a and the rear end cover of the dryer after service for 43 a was relatively long. The hardness of the cylinder and the end cover of the two dryers all met the standards. The tensile strength of the front end cover of the dryer after service for 62 a was lower than the standard requirements, while those of the other positions of the two dryers all met the standard requirements. The tensile strength of the front end cover of the dryer after service for 62 a and the rear end cover of the dryer after service for 43 a was obviously lower than that of other positions. Both the two dryers still had sufficient strength under the maximum working internal pressure load of 0.22 MPa.
  • Erosion Behavior of N80 Oil Well Tube Steel in 3.5wt% NaCl Solution
    ZHANG Yani, ZHANG Shaogang, LUO Jinheng
    Materials For Mechanical Engineering. 2021, 45(3): 35-40. https://doi.org/10.11973/jxgccl202103007
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The erosion behavior of N80 oil well tube steel in 3.5% NaCl solution was studied by weightlessness method and electrochemical test. The results show that the mass loss rate of N80 steel unchanged and then increased with increasing the stirring speed. The self-corrosion current density of N80 steel during erosion was significantly greater than that during immersion corrosion under the same times. The self-corrosion current density increased with extensing the immersion time, increased and then decreased with extensing the erosion time, and increased with increasing the dissolved oxygen. The corrosion effect of fluid on N80 steel in the early stage of erosion was dominant, and the impact of fluid was dominant in the middle and late stages. With extensing the erosion time, the corrosion products on the surface of N80 steel increased, the degree of plastic deformation at the edge of the corrosion pit increased, shape of the corrosion pit gradually changed from circular to elliptical, and the corrosion rate decreased. The surface hardness of N80 steel after erosion for 1 h was lower than that of the uneroded, and after erosion for 2 h, the hardness of N80 steel was higher than that of the uneroded due to the formation of a hardened layer on the surface of N80 steel.
  • Influence of Substrate Bias Voltage on Microstructure and MechanicalProperties of CrAlN Nano-mutilayer Film Prepared by Magnetron Sputtering
    WANG Yuxing, ZHANG Xia
    Materials For Mechanical Engineering. 2021, 45(3): 41-45. https://doi.org/10.11973/jxgccl202103008
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    CrAlN nano-multilayer films were prepared by magnetron sputtering technique under different bias voltages (-60,-70,-80,-90 V) of the substrate, and the effect of bias voltage of the substrate on the microstructure and mechanical properties of the film was studied. The results show that with increasing absolute value of the substrate bias voltage, the nitrogen content in the CrAlN nano-multilayer film increased, the phase composition unchanged, the preferred orientation changed from the CrN (111) crystal plane to the CrN (200) crystal plane, the pores on the film surface decreased, and the densification of microstructure was improved. When the bias voltage of the substrate was between -60 and -80 V, the bias voltage had little effect on the film deposition rate. When absolute value of the bias voltage was higher than 80 V, the deposition rate decreased significantly. With increasing absolute value of bias voltage of the substrate, the hardness and elastic modulus of the film increased, and the film base bonding force increased and then decreased, reaching the maximum at -80 V of bias voltage.
  • Type and Thickness of Copper Foli on Microstructure and Properties of Resistance Spot Welded Joints of Titanium/Steel
    ZHANG Pengxian, LU Jianqiang, CHEN Pei
    Materials For Mechanical Engineering. 2021, 45(3): 46-51. https://doi.org/10.11973/jxgccl202103009
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Resistance spot welding was performed on TC4 titanium alloy and 304 stainless steel sheet with copper foils of different types and thicknesses as transition layer materials. The influence of the type and thickness of the copper foils on the microstructure and properties of the joint was studied. The results show that the shear strength of the welding joint with pure copper foils as the transition layer was significantly higher than that of the copper alloy foils as the transition layer, and the welding joint with T4 copper foil as the transition layer had the highest shear strength. With increasing thickness of the T4 copper foil, the width of the reaction zone of the joint decreased, the width of the intermediate transition zone increased, and the Ti-Fe intermetallic compound in the fusion zone decreased, the shear strength of the joints increased first and then decreased, reaching the maximum when the thickness was 0.4 mm.
  • Formation Mechanism of Sn Whiskers in Mechanical Alloying MixedPowder of Ti, Sn, C
    LU Hailong
    Materials For Mechanical Engineering. 2021, 45(3): 52-55. https://doi.org/10.11973/jxgccl202103010
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The mixture of Ti powder, Sn powder and C powder with mass ratio of 2:1:1 was mechanically alloyed in a simoloyer mill, and then was treated by aging at room temperature. The phase composition, microstructure and formation mechanism of Sn whiskers in the mechanical alloying powder were studied. The results show that flocs appeared in the power mixture after mechanical alloying and aging at room temperature, and were composed of Sn whiskers. The Sn whiskers were columnar, collicular-shaped or nodular, knotted or curved, and needle-shaped single crystal β-Sn with body centered tetragonal structure. The whisker had a diameter of about 100 nm, and the zone axis was[011] zone axis of β-Sn. Under heat and huge stresses produced by mechanical alloying, the recrystallization and direct growth of Sn occurred, and then Sn whiskers were obtained.
  • Friction and Wear Properties of Different Nylon Under Different Conditions
    CHEN Baolei, JIA Tifeng, ZHOU Zhongshang, ZHANG Xiaoqiang
    Materials For Mechanical Engineering. 2021, 45(3): 56-60,75. https://doi.org/10.11973/jxgccl202103011
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    MC nylon, MC oil nylon containing 5% (mass fraction) of lubricating oil, and carbon fiber reinforced compound MC nylon containing 35% (volume fraction) of carbon fiber were prepared. The friction and wear performance of three kinds of nylon under dry friction, clean water, dry sand, and water sand conditions were studied. The results show that the friction factor and wear rate were the smallest of MC oil nylon under the four conditions due to the existence of lubricant film on the surface. Under the conditions of dry friction and water lubrication, the fiber protrusions on the surface of compound MC nylon made the wear rate and friction factor smaller than that of MC nylon. The degree of wear of nylon under water lubrication were lower than that under dry friction. Under the conditions of dry sand and water sand, the ploughing effect of quartz sand caused more furrows appeared on the surface of MC nylon. Only a few furrows appeared on the surface of MC oil nylon due to the lubricant oli film on the surface. The degree of wear of nylon under water sand conditions was lower than that under dry sand conditions.
  • Fatigue Performance of EA4T Steel Axle with Diamond Indentation of Different Size
    ZHANG Heng, YIN Hongxiang, WU Yi, LI Xiang
    Materials For Mechanical Engineering. 2021, 45(3): 61-65,82. https://doi.org/10.11973/jxgccl202103012
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Indentation defects were prefabricated on the bending fatigue specimen taken from EA4T steel axel by diamond indenter extrusion method. The influence of indentation depth on the fatigue strength was studied. The revised Murakami model was used to predict the fatigue strength and the fatigue indicator parameter was introduced to construct the fatigue life prediction model. The strain near indentation was analyzed by the finite element method. The results show that the fatigue strength of the sample decreased with increasing indentation depth. Compared with the sample without indentation, the fatigue strength was slightly reduced with the indentation depth of 0.052 mm, and significantly reduced with the indentation depth of 0.112 mm and 0.504 mm. The fatigue cracks were initiated at the prefabricated indentation short diagonal with large stress concentration, the finite element simulation results was accurate. The revised Murakami model could accurately predict the fatigue strength of the sample with indentation defect, and the constructed fatigue life prediction model had high accuracy. The ratio of the measured value to the predicted value was within the range of two times the error factor.
  • Study of Thermal-Mechanical Coupling Characteristics of Epoxy Resin Potting Structure
    ZHANG Guoliang, LI Yuefang, LI Xiang
    Materials For Mechanical Engineering. 2021, 45(3): 66-70,97. https://doi.org/10.11973/jxgccl202103013
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Mechanical and physical parameters and curing residual strain of epoxy resin potting material with curing temperature of 60℃ were tested at environmental temperatures of -30-60℃. Taking it as an input condition, the thermal strain of the epoxy resin potting structure was simulated by the finite element simulation, and the results were compared with the test results, and the thermal coupling characteristics of the epoxy resin potting structures were studied. The results show that the relative errors of the simulated thermal strain and the experimental thermal strain of the epoxy resin potting structure were both within the allowable range of the project, the finite element simulation results was accurate. The thermal stress in the range of -30-60℃ was far less than its fracture strength, and it would not crack due to thermal stress in the range of temperature.
  • Influence of Size of Honeycomb Structure on Poisson's Ratio and Energy Absorption
    YAN Xiaonan, WANG Rong, CHEN Yongxiong, CHENG Yanhai, LIANG Xiubing
    Materials For Mechanical Engineering. 2021, 45(3): 71-75. https://doi.org/10.11973/jxgccl202103014
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The compression process of the thermoplastic polyurethane elastomer honeycomb structure was simulated by the finite element model, and was verified by experiments. The influence of the cell concave angle, width and wall thickness on the Poisson's ratio and energy absorption of honeycomb structure was studied by this model. The results show that the model could simulate the compression process of the honeycomb structure accurately, and the relative error of the peak stress of test and simulation was within 10%. When the concave angle was negative, the honeycomb structure had negative Poisson's ratio, and the energy absorption was larger than that of honeycomb structures with positive concave angle. The smaller the cell width or the larger the cell wall thickness, the greater the energy absorption of the honeycomb structure. With the cell concave angle of -30°, the width of 1 mm, and the wall thickness of 1 mm, the honeycomb structure had the best energy absorption effect. The concave angle had the greatest influence on the Poisson's ratio and energy absorption of the honeycomb structure.
  • Tensile Properties Characterization of Micro-zone of 6061-T6 Aluminum Alloy MIG Welded Joint and Finite Element Simulation of Tensile Properties of Joint
    WANG Qianjin, XU Congchang, LI Jia, XU Hong, HE Hong, LI Luoxing
    Materials For Mechanical Engineering. 2021, 45(3): 76-82. https://doi.org/10.11973/jxgccl202103015
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A high precision equivalent experimental method for measuring micro-zone tensile properties of 6061-T6 aluminum alloy MIG welded joint was established. The temperature changed during the welding process was simulated by finite element, and relationship between temperature and tensile properties of joint micro-zone was established. The parameters that could characterize properties of each micro-zone material of joint was obtained, and verified that joint was equivalent to materials in different thermal states to established the fine model for predicting the properties of joint was reliability. The results show that the simulation of the temperature field, weld pool morphology and tensile properties were in good agreement with the experimental results. The error of the peak force between simulation by eguivalent weld joint and experiment was only 0.1%, and the displacement error of fracture failure was only 5.7%. The heat affected zone grid was divided into different thermal state materials on the basis of temperature distribution could effectively predict tensile properties of weld joint.
  • Dynamic Expansion Deformation Characteristics of Thin-Wall Aluminum Alloy Cylindrical Shell Driven by Electromagnetically
    XU Yongpeng, DONG Xinlong
    Materials For Mechanical Engineering. 2021, 45(3): 83-87. https://doi.org/10.11973/jxgccl202103016
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The magnetic pressure distribution and deformation characteristics during the dynamic expansion and deformation of aluminum alloy cylindrical shells with different axial heights driven by electromagnetic coils was analyzed by the ANSYS multiphysics coupling field finite element simulation, and compared with the experimental results. The results show that the finite element model could accurately simulate the radial magnetic pressure distribution and deformation of the cylindrical shell driven by the electromagnetic coil. When the height of cylindrical shell was 20 mm, the radial magnetic pressure at the end was greater than that in the middle, and occured concave uneven expansion. When the height of the cylindrical shell was 30, 40 mm, the radial magnetic pressure at the end was smaller than that in the middle, and occured convex uneven expansion. When the height ratio of the cylindrical shell and the coil was about 0.7, the radial magnetic pressure was basically the same at the end and middle, and distribution of radial magnetic pressure was uniform.
  • Puncture Cause of φ139.7 mm Drill Pipe Joint of a Directional Well
    YU Shijie, XU Changxue, CHEN Meng, OUYANG Zhiying
    Materials For Mechanical Engineering. 2021, 45(3): 88-92,102. https://doi.org/10.11973/jxgccl202103017
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    A drill pipe joint puncture event occurred during drilling in a directional well. The cause of the puncture was analyzed by microstructure and fracture morphology observation, chemical composition and mechanical properties test. The results show that the drill pipe was subjected to great bending stresses during the service, leading to stress concentration at the root of the 18° elevator shoulder of the drill pipe internal thread joint. Moreover, there were circumferential scratches at the root of the shoulder. Therefore fatigue cracks were originated and propagated. During the drilling of the drill pipe, the bending stress increased, resulting in the increase of the crack growth rate. The propagated cracks pierced the entire wall thickness, resulting in the puncture. It was suggested that optimizing the drill pipe structure and strictly controling the drill pipe processing technique to avoid scratches and reduce the stress concentration at the root of the shoulder.
  • Reasons for Corrosion Failure of S135 Steel Grade Drill Pipe in a Certain Well
    CHEN Meng, OUYANG Zhiying, YU Shijie
    Materials For Mechanical Engineering. 2021, 45(3): 93-97. https://doi.org/10.11973/jxgccl202103018
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The S135 steel grade drill pipe of a certain well suffered corrosion failure when the drilling distance was about 2 395 m. The fracture reason was analyzed by macromorphology and fracture morphology observation, microstructure analysis, and chemical composition, hardness, and corrosion product composition tests. The results show that the failure mode of the drill pipe was corrosion fatigue failure. The inner wall of the drill pipe had high oxygen content and stress concentration in the thickened transition zone of inner wall, resulting in severe pitting corrosion in the thickened transition zone. Fatigue cracks were initiated in the bottom of the pits and propagated, fainally leading to the failure of the drill pipe. It was recommended to use the drill pipe with anticorrosive coating of inner wall, add corrosion inhibitor to the drilling fluid to reduce the corrosion effect of dissolved oxygen on the inner wall, and optimize the well depth structure to reduce stress concentration.
  • Cause of Unevenness Saw Cutting Surface of 718 Plastic Mould Steel
    YAN Zhibo, HE Huimin, WANG Xiangming
    Materials For Mechanical Engineering. 2021, 45(3): 98-102. https://doi.org/10.11973/jxgccl202103019
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The saw cutting surface appeared unevenness problem of the 718 plastic mould steel. The reason for the uneven surface was analyzed by chemical composition test, microstructure morphology observation, micro-area composition analysis and hardness test. The results show that the segregation of chromium, manganese and molybdenum was primary cause of the uneven saw cutting surface. The segregation of element made the 718 plastic mold steel form a hard mirostructure composed of tempered martensite and tempered lower bainite, which was harder than that of the hard microstructure of the substrate, leading to the unevenness of the surface during the cutting process. It was suggested that reducing the segregation by increasing the cooling strength, or adding the homogenization heat treatment process to avoid this problem.
Quarterly Established in 1978
Sponsor:
ShangHai Ship and Shipping Research Institute Co,.Ltd.
ISSN 1674-5949
CN 31-2023/U
　 Copyright © Materials For Mechanical Engineering, All Rights Reserved.
Powered by Beijing Magtech Co. Ltd,.