活塞头部或“冠部”是整个活塞的最上端，处在燃烧室里要承受爆炸燃烧产生的力。

The piston head or "crown" is the top surface against which the explosive force is exerted.

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本发明公开了一种激光焊接活塞的方法，将分别制造的活塞头部和 活塞裙部，通过激光焊接连为一体；

The invention discloses a method for welding pistons by laser. The method comprises: a piston head and a piston skirt, which are respectively made, are welded into a whole by laser;

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而且气门头部容易被经过的高温气体烧蚀，活塞顶部也可能会碰到气门使发动机严重损坏。

Also the valve heads will be liable to be burnt by the passing hot gases, and there is the likelihood of the piston crown touching an open valve, which can seriously damage the engine.

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