The research showed that the structure of weld mark was connected with the material formulation, die mould of extrusion machine and parameters of processing technology.
研究发现，熔接痕的结构与材料配方、挤出机机头模具及加工工艺参数均有关系。
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Reading is not only a mark of a person's self-cultivation, but also an important way for people to mould themselves, perfect their characters, elevate their minds, and gain wisdom.