一、前言 目前国内使用的热挤盂底板模具钢一般为3Cr2W8V。这种钢,当使用温度超过65C℃时,由于基体回复和第二相质点的粗化,模具表面强度下降,产生早期塑性变形,降低使用寿命。如某厂3Cr2W8V钢底板,寿命只有200件左右。使用新型奥氏体模具钢代替3Cr2W8V钢制做底板,取得明显效果,使用寿命提高6倍以上。文献[1]指出, First, the preface At present, the domestic use of thermal extrusion die steel mold is generally 3Cr2W8V. This steel, when the use of temperature exceeds 65C ℃, due to the matrix and the second phase of the second phase of coarse particles, the surface strength of the mold decreased, resulting in early plastic deformation, reducing service life. Such as a factory 3Cr2W8V steel floor, life expectancy is only about 200 pieces. The use of new austenitic die steel instead of 3Cr2W8V steel floor, achieved significant results, the service life increased by 6 times. Literature [1] pointed out that,