斜轧穿孔法制备TC4合金管坯

TC4 Titanium Alloy Seamless Blooms Made by Rotary Piercing

为了供给市场要求的大直径TC4钛合金异型管壳的二次成形坯料,采用斜轧穿孔加工工艺制备了符合需求的TC4管坯。原始材料为自耗电弧熔炼铸锭,铸锭在β和α+β相区锻造成φ100mm×700mm的棒坯。穿孔前棒坯在中频感应炉中经980℃,3min热处理,然后在加强型两辊斜轧穿孔机上一火穿成φ102mm×11mm×1700mm管坯。所制成的管坯表面光滑,外径尺寸公差达到0.35mm,壁厚公差达0.1mm。管坯退火态室温下Rm=945MPa,A=14%,Z=33%。其强度比挤压制备的管坯略高,塑性相当。实验结果表明,采用斜轧穿孔法完全可以制备符合标准要求的大直径TC4管坯。

The method of rotary piercing for fabricating large size of TC4 titanium alloy seamless bloom is introduced here. The appearance quality, microstructure and mechanical properties of the blooms are investigated. As contrast, the properties mentioned above are also compared with that of blooms made by extrusion. The results indicate that the quality of blooms which fabricated by rotary piercing at intermediate frequency induced heating is superior to that of the extrusion blooms in appearance inspection and dimensional tolerance; the mechanical properties of the piercing-made blooms both at room and high temperature meet the standard specification, and are as good as that of blooms fabricated by extrusion.