Hot deformation behavior of the 1.15C-4.00Cr-3.00V-6.00W-5.00Mo powder metallurgy high speed steel

详细信息    查看全文

• 作者：Yanhui Liu ; Yongquan Ning ; Zekun Yao ; M.W. Fu
• 关键词：Powder metallurgy high speed steel ; Hot workings ; Constitutive modeling ; Hot workability ; Advanced processing maps
• 刊名：Materials and Design
• 出版年：February, 2014
• 年：2014
• 卷：54
• 期：Complete
• 页码：854-863
• 全文大小：5925 K

文摘

The deformation behavior of the 1.15C-4.00Cr-3.00V-6.00W-5.00Mo powder metallurgy (PM) high speed steel in hot working process was investigated by the isothermal compression tests carried out at the temperature of 950-1150 掳C and the strain rate of 0.001-1.0 s^鈭? with the height reduction of 60%. True stress-true strain curves are investigated; the hot deformation activation energy of the steel is determined to be 750 kJ/mol, and a constitutive equation is obtained. The processing maps were constructed, identification of the instability region and optimization of hot deformation parameters. It is found that the hot working process of the steel can be carried out safely in the domain of (T_d: 1000-1150 掳C, : 0.006鈭?.1 s^鈭?). To obtain the homogeneous microstructure with fine grains, the hot working process should be carried out at the condition of (T_opi: 1050 掳C, : 0.1 s^鈭?). The flow instability is expected in the two domains at 1030-1150 掳C/0.1-1.0 s^鈭? and 1000-1075 掳C/0.001-0.006 s^鈭?. Furthermore, the true strain takes a great effect on processing maps in which the efficiency of power dissipation 畏 obviously changes with the increase of strain from 0.05 to 0.90.