摘要
通过连续冷却转变曲线的绘制、焊接冷裂纹敏感性试验以及从800℃冷却到500℃的时间(t8/5)对焊接粗晶热影响区(CGHAZ)韧性的影响等方法,系统评价了一种960 MPa级工程机械用钢的焊接性能。结果表明:工程上配套使用GHS-90实心焊丝,在φ(Ar)80%+φ(CO2)20%混合气体保护下焊接,需将该钢板预热至200℃以上才能避免焊接冷裂纹倾向(钢板厚度为20 mm);t8/5>20 s后,粗晶区韧性严重降低;通过制定合理焊接工艺可满足960 MPa强度级别的工程使用要求。
The welding performance testing of 960 MPa grade machinery steel was systematically investigated by following methods: drawing the curve of CCT,testing the cold cracking sensifivity of welding and effect of the cooling time from 800 ℃ to 500 ℃(t8/5) on toughness variation of the CGHAZ.The results showed that,the cold cracking propensity of welding could be avoided by raising preheating temperature to more than 200℃ in engineering (plate thickness 20 mm),that was compatible with the solid wire GHS-90 for φ(Ar) 80%+φ(C02)20% shielded arc welding;the toughness variation of the CGHAZ was rapidly decreased while the t8/5 was up to 20 s;though made the reasonable welding process,the 960 MPa grade machinery steel could be used in engineering field,successfully.
出处
《电焊机》
北大核心
2012年第7期1-6,共6页
Electric Welding Machine
关键词
焊接性能
预热温度
焊接裂纹敏感性
CGHAZ
welding performance
preheating temperature
cracking sensitivity of welding
CGHAZ