摘要
采用Gleeble-1500热模拟试验机测试了含钒低合金钢铸坯的高温延塑性,利用扫描电镜、金相显微镜对断口形貌及金相组织进行分析。低合金钢的第Ⅰ脆性温度区在Ts^1 370℃之间,第Ⅲ脆性温度区在915~710℃之间。第Ⅲ脆性区间由奥氏体低温域晶界滑移楔形裂纹造成的沿晶脆性断裂和奥氏体晶界先共析铁素体薄膜造成的沿晶韧性断裂两部分组成。钢中的V对钢的第Ⅲ脆性凹槽的影响比较大,脆化向低温区域延伸。
The hot ductility of vanadium containing microalloy steel continuous cast slab was investigated with Gleeble-1500 tensile test machine,the fracture surface and metallurgiclical structure were analyzed by SEM and optical microscope. It was found that the low ductility temperature region I of low alloy steel is between the Ts and 1 370 ℃ and the low ductility region III is between 915 ℃ and 710℃. The embrittlement in region III was made up of intergranular brittle fracture caused by the grain boundary sliding in the single phase austenite region followed by wedge cracking and intergranular toughness fracture caused by precipitation of proeutectoid ferrite film along austenite grain boundary. Vanadium largely affects the ductility of the steel in the low ductility temperature region III and cause the embrittlement extending to lower temperature.
出处
《中国冶金》
CAS
2010年第3期11-17,23,共8页
China Metallurgy
