冷轧加工对工业纯钛板焊缝组织与性能的影响

采用等离子弧焊将两张3.5 mm厚纯钛板对焊,然后在1 780 mm冷轧机上依次进行变形量为43%、50%的冷轧加工,且冷轧后均进行退火处理。对两个轧程的冷轧态及退火态焊缝试样进行了金相显微组织观察;对两个轧程退火态试样进行了室温力学性能及硬度测试;对退火态成品母材区和焊缝加工区进行了杯突试验和在3.5%NaCl水溶液中的阳极极化试验。结果表明,两次冷变形板材退火后焊缝加工区晶粒尺寸均比母材区略微细小,强塑性略好一些,维氏显微硬度也稍高一些;成品板材焊缝加工区的延伸率与母材相差不大,杯突值相近,具有与母材相当的工艺性能;成品板材焊缝加工区的阳极极化行为与母材无明显差异,二者在3.5%NaCl水溶液中的耐腐蚀性基本一致。

Effect of Cold Deforming on Microstructures and Properties of Commercial Pure Titanium Plates Welds

Pure titanium sheets of 3.5 mm thick were welded by plasma arc welding and cold rolled with 1 780 mm roller and then annealed. The sheets were first cold deformed by 43% and annealed, then cold deformed by 50% and annealed. Metallographs of welds after each rolling and annealing process were observed. Vickers hardness and mechanical properties at room temperature of welding area and base material after each annealing process were also investigated. Cup drawing tests and anodic polarization tests in 3.5% NaC1 solution of base material and welding area of second annealing process were applied. The results show that the grain size of wehling area after each annealing process was smaller compared with base material, while the strength, ductility and vickers hardness were little better than base material. After second rolling and annealing process, the elongation and cup-drawing value of welding area were close to base material. And the behavior in the anodic polarization tests of welding area were similar to base mate- rial, the corrosion resistance of base material and welding area in 3.5% NaC1 solution were basically consistent.