双相不锈钢焊接热影响区的TEM分析
来源期刊:中南大学学报(自然科学版)1996年第1期
论文作者:李健纯 蒲熙 Y.Riquier
文章页码:56 - 60
关键词:微结构; 透射电子显微术; 不锈钢; 焊接; 热影响区
Key words:microstructure; TEM; stainless steel; welding; heat affected zone
摘 要:对超级双相不锈钢 (Zeron100)焊接的热影响区进行了透射电镜TEM分析.采用的焊接条件为:厚板(18mm)多道埋孤对焊,单位长度热流量为1.49kJ/mm. 确定了在热影响区中存在Cr2N,CrN,Sigma,Chi,π等析出相。其中,立方氮化铬(CrN)系首次在此钢中观察到,在熔焊线附近发现有 Si,Al,Cr等元素的偏聚物.由本研究可知,此种材料的可焊性良好.
Abstract: The microstructure of the heat affected zone (HAZ). of a super duplex stainless steel (SDSS) has been investigated by means of optical and analytical electron microscopy. Heat input 1. 49 kJ/mm was performed on heavy plates (18 mm thick) employing multipass submerged arc welding. The most deleterious intermetallic phases such as Sigma phase, chromium nitrides (Cr2N and CrN), Chi and πphases are identified in the HAZ, yet the particle size and the volume fraction of these phases are very limited. The majority of precipitates inthe HAZ is secondary austenite. Cubic chromium nitride(CrN) has also been found. π phase was detected more often, implying sluggish cooling of the HAZ at lower temperatures. The microstructure of the HAZ reveals that it coincides with the mechanical properties and the corrosion behaviors examined. It is suggested that the weldability of this SDSS is reasonably good and the welding conditions chosen are acceptable.