Some samples of B1500HS boron steel austenizing at 900 ℃ are compressed about 10%, 20%, 30% and 40% at a constant strain rate by Gleeble 1500D thermo-mechanical simulator. The deformed samples are cooled at the rate of 50 ℃/s, 40 ℃/s and 25 ℃/s, the effects of deformation and cooling rate on the phase-transformation temperature, micro-structure, micro-hardness and retained austenite are researched. The results show that, the start and finish temperatures of martensite phase-transformation rise with increasing the deformation degree at the same cooling rate. The size of martensite microstructure becomes smaller, less twin martensite and more lath martensite are produced in the microstructure with increasing the deformation degree. The increase of deformation and cooling rate are both helpful to reduce the volume fraction of retained austenite in the samples of B1500HS steel. The continuous cooling transformation diagrams of B1500HS steel moves to left due to the deformation. The critical cooling rate for the undeformed austenite of B1500HS steel not transformed into bainite is approximately 25 ℃/s. If the deformation degree of B1500HS steel specimen is more than 30 %, bainite can be produced in the microstructure at the cooling rate of 25 ℃/s.
LI Huiping
,
HE Lianfang
,
YANG Xiaodan
,
ZHAO Guoqun
. Effect of Deformation and Cooling on the Phase Transformation of Martensite for B1500HS Boron Steel[J]. Journal of Mechanical Engineering, 2016
, 52(10)
: 67
-74
.
DOI: 10.3901/JME.2016.10.067
[1] 李辉平,赵国群,贺连芳,等. 热冲压硼钢B1500HS高温本构方程的研究[J]. 机械工程学报,2012,48(8)：21-27.
LI Huiping,ZHAO Guoqun,HE Lianfang,et al. Research on the constitutive relationship of hot stamping boron steel B1500HS at high temperature[J]. Journal of Mechanical Engineering,2012,48(8)：21-27.
[2] NADERI M,DURRENBERGER L,MOLINARI A,et al. Constitutive relationships for 22MnB5 boron steel deformed isothermally at high temperatures[J]. Materials Science and Engineering A,2008,478(1-2)：130-139.
[3] SO H,FABMANN D,HOFFMANN H,et al. An investigation of the blanking process of the quenchable boron alloyed steel 22MnB5 before and after hot stamping process[J]. Journal of Materials Processing Technology,2012,212(2)：437-449.
[4] ABDULHAY B,BOUROUGA B,DESSAIN C,et al. Experimental study of heat transfer in hot stamping process[J]. International Journal of Material Forming,2009,2(1)：255-257.
[5] 李辉平,贺连芳,赵国群. 硼钢B1500HS 界面传热系数与压力关系的研究[J]. 机械工程学报,2013,49(16)：78-83.
LI Huiping,HE Lianfang,ZHAO Guoqun. Research on the surface heat transfer coefficient depending on surface pressure of boron steel B1500HS[J]. Journal of Mechanical Engineering,2013,49(16)：78-83.
[6] MERKLEIN M,LECHLER J. Investigation of the thermo-mechanical properties of hot stamping steels[J]. Journal of Materials Processing Technology,2006,177(1-3)：452-455.
[7] 常颖,靳菲,李晓东,等. 车用热成形先进高强度钢板样件的热胀形特征及成形性分析[J]. 机械工程学报,2014,50(24)：73-78.
CHANG Ying,JIN Fei,LI Xiaodong,et al. Thermal expansion analysis based on forming limit diagram for improving the formability of automotive hot-forming advanced high strength steel parts[J]. Journal of Mechanical Engineering,2014,50(24)：73-78.
[8] MIN Junying,LIN Jianping,TIAN Haobin,et al. Investigation on uniaxial tensile instability of USIBOR1500 steel sheets at elevated temperature[J]. Chinese Journal of Mechanical Engineering,2010,23(1)：94-99.
[9] BARCELLONA A,PALMERI D. Effect of plastic hot deformation on the hardness and continuous cooling transformations of 22MnB5 microalloyed boron steel[J]. Metallurgical and Materials Transactions A,2009,40(5)：1160-1174.
[10] NIKRAVESH M,NADERI M,AKBARI G H. Influence of hot plastic deformation and cooling rate on martensite and bainite start temperatures in 22MnB5 steel[J]. Materials Science and Engineering A,2012,540：24-29.
[11] KELLY P M,JOSTSONS A,BLAKE R G. The orientation relationship between lath martensite and austenite in low carbon,low alloy steels[J]. Acta Metallurgica Materialia,1990,38(6)：1075-1081.
[12] 陈俊,吕梦阳,唐帅,等. V-Ti微合金钢的组织性能及相间析出行[J]. 金属学报,2014,50(5)：524-530.
CHEN Jun,LÜ Mengyang,TANG Shuai,et al. Microstructure,mechanical properties and interphase precipitation behaviors in V-Ti microalloyed steel[J]. Acta Metallurgica Sinica,2014,50(5)：524-530.
[13] 王学伦,宋介中,王巍. 二相粒子/析出相钉扎晶界模型研究进展[J]. 钢铁研究学报,2010,22(12)：1-6.
WANG Xuelun,SONG Jiezhong,WANG Wei. Development of analytical model for grain boundary pinned by second-phase particle[J]. Journal of Iron and Steel Research,2010,22(12)：1-6.
[14] POND R C,MA X,HIRTH J P. Geometrical and physical models of martensitic transformations in ferrous alloys[J]. Journal of Materials Science,2008,43(11)：3881-3888.
