论文部分内容阅读
虽然直接的借改变金属或间接的借改变表面状态(涂*以金属或非金属保护层)以及改变腐蚀的外在因素(处理腐蚀介质或采取电化学保护等)都能提高合金的耐蚀性,但是当金属构件在苛刻的条件下或是在腐蚀性特别强的介质中工作时,只有直接的提高合金本身的耐蚀性才是最有效的,有时甚至是唯一的防腐方法。用冶金手段来提高合金的耐蚀性目前可采取如下四种措施:(1)提高金属的纯度;(2)采取有效的热处理工艺;(3)冷加工;(4)合金化。提高金属纯度常常能提高合金的耐蚀性,例如最纯的锌在H_2SO_4溶液中,最纯的铝在HCl溶液中,最纯的镁在NaCl
Although the direct or indirect by changing the surface by changing the surface state (coated with metal or non-metallic protective layer) and change the corrosion of the external factors (processing of corrosive media or electrochemical protection, etc.) can improve the corrosion resistance of the alloy However, when the metal parts work under harsh conditions or in highly corrosive medium, it is only the most effective and sometimes the only anticorrosive method to directly improve the corrosion resistance of the alloy itself. Metallurgical means to improve the corrosion resistance of the alloy can now take the following four measures: (1) to improve the purity of metals; (2) to take an effective heat treatment process; (3) cold work; (4) alloying. Increasing the purity of the metal often improves the corrosion resistance of the alloy, for example, the purest zinc in H 2 SO 4 solution, the purest aluminum in HCl solution, the purest magnesium in NaCl