合金钢奥氏体混晶的形成与消除

Generating and Removing of Austenitic Mixed Grain in Alloy Steels

本文系统地研究变形温度和变形量对18Cr2Ni4wA钢奥氏体晶粒度的影响。研究指出,变形温度约1000℃以上,在任何变形量下,均可以获得级别较高的细晶粒,而在约950℃以下变形,变形量越大,混晶越严重。 本文还研究了不同锻造温度下,预处理工艺对奥氏体晶粒度的影响。研究表明:锻造后直接进行710℃高温回火,或者进行850℃正火+710℃高温回火,均能有效地改善或消除混晶现象。

The influence of the temperature and degree of deformation on the austenitic grain size was studied for 18Cr2Ni4wA Steel. It is shown that a higher grade of fine grains can be obtained above 1000℃ of deformation temperature, whatever the degree of deformation may be. The extent of mixing grain becomes more serious below 950℃ if increasing the degree of deformation. And the greater the degree of deformation, the stronger the mixed grain.In addition, the effect of pretreatment on austenitic grain size at different temperatures of forging was analyzed, showing that process of forging followed by tempering at 710℃ or normalizing at 850℃ + tempering at 710℃ may be used to remove and improve mixing grains.