Ni-Al自蔓延反应过程分析及电化学耐硫酸腐蚀性研究

Analysis of SHS Ni-Al reaction process and study on electrochemical corrosion resistance

选取Ni、Al粉末按照原子比为1:1、3:1分成两组,压制成坯,采用激光引燃自蔓延反应,并用XRD对生成物试样进行化合物成分分析,用恒电位法对生成物进行耐腐蚀性测试.结果表明:Ni、Al原子比为3:1,生成金属间化合物Ni3Al;原子比为1:1,生成金属间化合物NiAl;且NiAl耐腐蚀性高于Ni3Al,其自腐蚀电位达244mV,维钝区间达1 300mV,维顿电流达0.086 3mA/mm2.

The Ni, A1 powder is divided into two groups in accordance with the atomic ratio of 1 ： 1 and 3 ： 1, and compressed into a billet using laser ignited self-propagation reaction. The resultant composition of test sample is analyzed by XRD and the corrosion resistance tested by potentiostatic method. The results show that： The powder of Ni, A1 generated Ni3A1 when the atomic ratio is 3 ： 1; it can generate NiA1 when the atomic ratio is 1 ： 1. Then NiA1 is better than Ni3A1 in corrosion resistance. The data of NiA1 is as follows： the free-corrosion potential is 244 mV; the value of passivation region is 1 300 mV;the value of maintaining passivity current density is 0. 086 3 mA/mmz.