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看了木刊1963年7月号“提高锡青銅鑄件性能的探討”(以下简称“原文”)一文后,有几点补充和商榷意見。一、銅本身的机械性能对合金性能的影响錫青銅是目前我国采用较广的一种銅合金,长期以来有着一定的生产經驗。但由于它的結晶間隔比较寬大,合金材料結构本身决定了它的鑄件容易产生組織疏松、渗漏、裂紋、强度低等現象。因此在鑄造工艺特性方面,要认識到合金冷却凝固結晶机理的条件,在接近凝固温度时合金成为糊状,所以在鑄造过程中流动性较差;当然它与一般結晶間隔狹小的鋁銅合金相比,組織一般呈現树状結晶,鑄件冷却凝固过程中集中补縮性差,即使采用相当大的冒口也不会得到组织致密性高的鑄件,尤其高压力鑄件更难,因此在生产这类合金鑄件时,提高机械性能确是值得研究的问题。
After reading Wood’s July, 1963 issue of “Discussion on Improving the Performance of Tin Bronze Castings” (hereinafter referred to as the “original”), a few comments were added and discussed later. First, the mechanical properties of copper on the performance of the alloy Tin bronze is a widely used in our country a copper alloy, has a long history of production experience. However, due to its relatively large crystallization interval, the alloy material itself determines the structure of its castings prone to loose, leakage, cracks, low intensity and so on. Therefore, the casting process characteristics, we must recognize that the alloy cooling solidification crystallization conditions, the alloy near the solidification temperature into a paste, so in the casting process less fluid; of course, it is generally small interval with the crystallization of aluminum-copper alloy In contrast, the organization generally presents dendritic crystals, which are poorly concentrated during cooling and solidification of castings. Even relatively large risers can not obtain highly dense castings, especially high-pressure castings. Therefore, in the production of such Alloy casting, to improve the mechanical properties is indeed worth studying.