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研究了DZ40M钴基合金低压气相沉积简单铝化物和钛改性铝化物2种涂层的形成及其高温氧化时的相变退化过程。结果指出：沉积涂层外层是CoAl相，内层是富Cr的碳化物连续带。高温下，涂层经历着CoAl→CoAl（主）＋a-Co→α-Co（主）＋CoAl→α-Co的相变过程。涂层内部α-Co的出现，标志退化开始，CoAl完全转变成α－Co，即退化结束。渗剂中加入Ti，降低了Al的活性，使得形成的涂层中Al的含量和涂层厚度都相应减小，涂层的高温退化加速。
The formation of two kinds of coatings of simple aluminides and titanium modified aluminides by low pressure vapor deposition of DZ40M cobalt base alloy and the transformation degeneration process during high temperature oxidation were studied. The results show that: the outer coating layer is CoAl phase, the inner layer is Cr-rich carbide continuous belt. Under high temperature, the coating undergoes the transformation of CoAl → CoAl (main) + a-Co → α-Co (main) + CoAl → α-Co. The appearance of α-Co inside the coating marked the beginning of degradation and CoAl completely transformed into α-Co, that is to say, the degradation was completed. Addition of Ti to the penetration agent reduces the Al activity, so that the Al content and the coating thickness in the formed coating decrease correspondingly, and the degradation of the coating accelerates at high temperature.