Abstract: The effect of austenitic treatment at 860 ~ 980 °C on microstructure of steel 30CrSiMnNiWMo (% :
0. 28C, 0. 74Mn, 1. 04Si, 2. 70Cr, 1. 15Ni, 0. 45Mo, 1.04W, 0. 07V, 0. 05Al) and mechanical properties of steel tempered at 260 °C has been studied. Results show that there are a lot of carbide M6C in microstructure of steel 30Cr3SiMnNiWMo quenched at 860 ~ 920 °C led to slightly decrease toughness of tempered steel, and after quenched at 950 °C , the carbides in steel are basically dissolved and the original austenite grains of steel beginning coarsen led to de- crease strength of tempered steel ； with oil quenched at 920 ℃ for 1 h + tempered at 260 °C for 2 h, the steel 30Cr3SiMnNiWMo has lath martensite microstructure with minor residual austenite and un-dissolved carbides, so it has excellent strength and toughness i. e. UTS- 1 680 MPa, YS- 1 330 MPa, elongation- 13% , RA- 58. 3% and impact energy- 85 J.

摘要： 试验研究了860～980℃奥氏体化处理对30Cr3SiMnNiWMo钢(%:0.28C、0.74Mn、1.04Si、2.70Cr、1.15Ni、0.45Mo、1.04W、0.07V、0.05Al)组织以及260℃回火后钢的力学性能的影响。结果表明,30Cr3SiMnNiWMo钢860～920℃淬火组织中存在大量M6C碳化物,对回火钢的韧性不利;950℃淬火后,钢中M6C碳化物基本溶解,原奥氏体晶粒开始长大,回火后钢的强度降低;30Cr3SiMnNiWMo钢经920℃1h油淬+260℃2h回火可以获得具有少量残余奥氏体和未溶碳化物的板条马氏体组织,并具有优良的强韧性(Rm=1680 MPa, Rp0.2=1330 MPa,A=13%, Z=58.5%, AKU=85 J) 。