论文部分内容阅读
采用激光焊接方法对Fe-Mn-Al-Si系TWIP钢进行焊接,观察和测定了接头的微观组织和硬度,研究了接头的拉伸、冲击性能及断裂行为。结果表明,在拟定焊接工艺下,TWIP钢接头无明显热影响区,焊缝区晶粒发生细化且平均硬度值最大;接头伸长率低于母材,拉伸断裂发生在母材区域;TWIP钢在-196℃以上温度区间均表现出良好的冲击韧性;接头在-117℃以上温度区间的冲击性能与母材相当,但在-196℃时,接头的冲击吸收功大幅下降,断口上观察到脆性断裂特征。
The welding of Fe-Mn-Al-Si TWIP steel was carried out by laser welding. The microstructure and hardness of the joint were observed and measured. The tensile, impact and fracture behaviors of the joint were studied. The results show that there is no obvious heat affected zone in the TWIP steel joints under the proposed welding process, the grain size of the weld zone is refined and the average hardness value is the highest, the joint elongation is lower than the base metal, and the tensile fracture occurs in the base metal. TWIP steel showed good impact toughness at the temperature above -196 ℃. The impact performance of the joint at -117 ℃ was similar to that of the base metal. However, at -196 ℃, the impact absorption energy of the joint decreased sharply, Brittle fracture characteristics were observed.