DH360Re高强韧热作模具钢的组织和性能

Structure and Properties of DH360Re High Strength and Toughness Hot Work Die Steel

分析了退火态DH360Re模具钢的显微组织,利用JmatPro软件计算了其相变特性及临界转变温度;对试验钢进行淬火+回火热处理,研究了不同热处理工艺下的硬度、冲击韧性、热稳定性和抗氧化性能.结果表明:退火态试验钢的显微组织为铁素体基体和分布于基体上的细小球状碳化物;经1020℃淬火,再依次进行540℃,580~600℃,570℃三次回火后,试验钢获得优良的强韧性(硬度50~54 HRC,无缺口冲击功不低于300J,夏比V型缺口冲击功不低于15J);经1020℃淬火,再依次进行540,590,570℃回火处理后,试验钢能够在650℃以下长期保持高硬度,在600℃以下的氧化脱碳进程缓慢,热稳定性和抗氧化性能良好.

The microstructure of annealed DH360 Re die steel was analyzed and the phase transformation characteristics and critical temperature were calculated by JmatPro software.The test steel was quenched and tempered,and the hardness,impact toughness,thermal stability and oxidation resistance under different heattreatment conditions were studied.The results show that the annealed test steel had a microstructure composed of ferrite matrix and fine spheroidized carbides distributing in the matrix.After quenching at 1020℃and three-time tempering at 540℃,580-600℃and 570℃,in turn,the test steel obtained excellent strength and toughness(hardness of 50-54 HRC,notchless impact energy of no lower than 300 J,and notched impact energy of no lower than 15 J).After quenching at 1020℃and tempering at 540℃,590℃and 570℃,in turn,the test steel maintained high hardness for a long time below 650℃and had a slow oxidation decarburization process below600℃,indicating good thermal stability and oxidation resistance.