我厂对于薄紫铜管或紫铜板的接头,一直采用H62黄铜焊条钎焊,加热用乙炔—氧焊炬。这种钎焊方法具有操作简便,劳动条件好,焊缝美观,强度高等优点。但是,有时遇到一批T_2铜材,按图纸要求检验,化学成分合格,却难以进行钎焊,钎焊时溶化的焊条,不能象通常那样容易润湿紫铜表面,焊完后焊缝接头强度不够,抗拉强度一般为15～19kg/mm~2,尤其是对焊缝进行弯曲试验时,都从焊条金属覆盖下的紫铜表面发生开裂。经金相分析,发现在紫铜中,以氧化亚铜(Cu_2O)形式存在的氧达到0.03％以上(GB471—64规定T_2含氧量≤0.06％)。因此我们对这个问题进行了分析研究。 1、钎焊时溶化的焊条为什么有的难 Our factory for thin copper or copper plate connector, has been using H62 brass brazing, heating with acetylene - oxygen torch. This brazing method has the advantages of simple operation, good working conditions, beautiful weld appearance and high strength. However, sometimes encountered a number of T_2 copper, according to the requirements of the test drawings, chemical composition of qualified, but difficult to braze, brazing welding electrode can not be as easy as wetting the surface of copper, welded joints after the weld strength Not enough, the tensile strength is generally 15 ~ 19kg / mm ~ 2, especially when the weld is subjected to the bending test, cracking occurs from the surface of the copper covered by the electrode metal. Metallographic analysis showed that in the copper, the presence of oxygen in the form of cuprous oxide (Cu 2 O) reached more than 0.03% (GB 471-64 stipulated T 2 oxygen content ≤ 0.06%). Therefore, we conducted an analysis on this issue. 1, soldering electrode dissolved why some difficult