摘要
G13Cr4Ni4Mo4VA轴承钢(/%:0.13C,4.13Cr,3.52Ni,4.39Mo,1.19V)由6 t真空感应炉+1.3 t(Φ406 mm)真空自耗炉熔炼,并经锻造(1160℃加热,≥1140℃开锻,≥900℃终锻)生产成中120 mm棒材。力学性能试样经1 100℃80 min淬火(N_2气冷),-73℃2 h冷处理,3次回火:550℃2 h空冷处理。其冲击值a_(ku)为27.1~39.5 J/cm^2,低于标准87.5 J/cm^2要求。经试验得出,由于锻造温度过高,造成δ铁素体在晶界的析出,使棒材冲击性能降低。通过锻造工艺优化,将钢锭加热温度由原1160℃降至1 110℃,避免δ铁素体的析出,棒材的平均a_(ku)冲击值提高至113.6 J/cm^2。
The bearing steel G13Cr4Ni4Mo4VA (/% : 0. 13C, 4. 13Cr, 3.52Ni, 4. 39Mo, 1.19V) is melted by 6 t vacuum induction furnace + 1.3 t ( Ф406mm) vacuum are remelting furnace, and forged to Ф120 mm bar with heating at 1 160 ℃, beginning forging at ≥1 140 ℃ and end forging at ≥900 ℃. The specimen for mechanical properties examina- tion is quenched at 1 100 ℃ for 80 rain ( N2 gas cooling) , cold treated at - 73 ℃ for 2 h and 3 times tempering treated at 550 ℃ for 2 h, air cooling. The impact value aku is 27. 1 -39. 5 J/cm2 , lower than that of requirement of standard i. e. 87.5 J/cm2. It is obtained by test that due to higher forging temperature, led to δ ferrite precipitating at grain boundaries, the impact value of bar decreases. With optimizing forging process, decreasing ingot heating temperature to 1 110 ℃ from original 1 160 ℃ to avoid the δ ferrite precipitation, the average impact value aku of bar increases to 113.6 J/cm2.
出处
《特殊钢》
北大核心
2015年第6期56-58,41,共4页
Special Steel
基金
国家863项目资助(2012AA03A503)