热处理对铁基激光熔覆层力学及耐腐蚀性能的影响

Effect of Heat Treatment on Mechanical and Anti-Corrosion Properties of Fe-Based Laser Cladded Coatings

在Q235碳钢上采用脉冲激光器制备出了铁基熔覆层,探究了不同热处理温度(600,750,900℃)对熔覆层的影响,对熔覆层的微观形貌、相组成和力学性能进行了表征,并探究了不同热处理温度下的熔覆层腐蚀行为。结果表明,熔覆层由结晶组织和非晶组织组成,结晶相随热处理温度的升高而增多;热处理会提高熔覆层近表面的硬度,其中经过900℃×2h热处理的熔覆层近表面平均硬度最高,约为1100 HV0.1;熔覆层的耐腐蚀性能随着热处理温度的上升而提高其中900℃×2h热处理后的铁基熔覆层具有最高的自腐蚀电位(-0.52500 V)和最低的自腐蚀电流密度(2.2810×10^-6A/cm^2),耐腐蚀性能最好。

Herein,Fe-based cladd ing coatings are prepared on Q235 carb on steels using a pulsed laser.The effects of heat treatment temperatures of 600℃,750℃,and 900℃on these coatings are investigated.In addition,the microstructures,phase compositions,and mechanical properties of these coatings are characterized.Moreover,the corrosion behaviors of these coatings before and after heat treatment are examined.The results show that after heat treatment,the coatings were observed to consist of both crystalline and amorphous structures.The content of the crystalline phase increases with the increase of heat treatment temperature,and heat treatment can increase the near surface hardness of cladding layers,specifically,the average hardness of cladding layers is the highest at approximately 1100 HV0.1 under the heat treatment of 900℃for 2 h.The anti-corrosion performance of coatings improves with the increase of heat treatment temperature,and the Fe-based cladding layers after heat treatment of 900℃for 2 h show the highest corrosion potential of 0.52500 V,the lowest corrosion current density of 2.2810×10^-6A/cm^2,implying the highest anti-corrosion performance.