问题 名词解释

钎焊

答案

参考答案:

是采用比母材熔点低的金属材料作钎料,将焊件和钎料加热到高于钎料熔点、低于母材熔点的温度,利用液态钎料润湿母材,填充接头间隙并与母材相互扩散实现连接焊件的方法。

材料题

阅读下列材料:

       材料一:“尽道隋亡为此河,至今千里赖通波”

       材料二:“北通涿郡之渔商,南运江都之转榆,其利也博哉。”

请回答:

(1)材料一中的“河”是指什么?

                                                                                                                                                             

(2)此“河”是谁在位时开通的?

                                                                                                                                                            

(3)此河开通后有什么作用?

                                                                                                                                                             

(4)材料二中的“涿郡”、“江都”分别是指现在的什么地方?

                                                                                                                                                            

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