超塑性TC4钛合金板中的α相晶粒, 在尺寸比较细小时, 采用常规的侵蚀剂不能有效显示其晶界。试验结果表明：分别采用阳极氧化镀膜法和化学沉积法, 在TC4钛合金板金相试样抛光表面沉积一层透光薄膜, 透过薄膜上光的干涉效应产生的组织间衬度可以真实、完整、清晰地显示α相晶粒形貌。并运用此方法得到了满足超塑性要求的TC4钛合金板晶粒尺寸金相图谱。

When the α-grain size of surperplastic TC4 titanium alloy plates is too small, the grain boundries would not be displayed effectively by the common etching reagents. The experimental results show that a layer of transparent film could be deposited on the polished surface of TC4 titanium alloy metallographic samples by anodic oxidation coating method or chemical deposition method, and the interference effect of light through the film could display the α-grain morphology vividly, completely and clearly. By these two methods, the metallograph of grain size of TC4 titanium alloy plates which met the superplastic forming requirements was obtained.