英语语法分析

The result proves that the accumulate line is caused by heat treatment defect, soft troostite tape.

结果表明，活塞杆在磁粉探伤中显现的螺旋形磁粉堆积线是由热处理缺陷一屈氏体软带造成的。

And in its transition zone, the hardness is remarkably reduced owing to the troostite precipitated.

过渡区由于发生托氏体转变，硬度明显下降。

The mechanical properties testing, microstructure observation and fractographic features analysis of the troostite high chromium cast iron blade were carried out.

通过金相、性能和热处理试验，对盘条拉丝断裂原因进行了分析，认为盘条存在屈氏体组织是断裂的根本原因。