火焰喷涂用Al-6Si丝材热处理工艺及涂层性能研究

Study on Heat Treatment Process and Coating Properties of Al-6Si Wire for Flame Spraying

采用拉拔的方法制备了火焰喷涂用Al-6Si丝材,研究了中间退火和成品退火温度对铝硅合金性能的影响,并对铝硅合金丝材涂层性能进行研究,对退火后铝硅合金坯料抗拉强度和伸长率进行测试,对退火后的成品铝硅合金丝金相组织进行了分析表征,并对自制Al-6Si丝材和进口铝硅丝材(Metco SF Aluminum)涂层的孔隙率、显微硬度、结合强度及热震性能进行分析比较。结果表明,铝硅合金坯料采用450℃退火工艺显著改善了力学性能,铝硅合金丝材经400℃退火处理,晶粒均匀。采用自制Al-6Si丝材和进口铝硅丝材喷涂涂层孔隙率、显微硬度、结合强度及热震等性能基本相当,满足封严涂层应用要求。

The Al-6Si wire for flame spraying was prepared by drawing method. The effects of intermediate annealing and finished product annealing temperature on the properties of Al-Si alloy were studied, and the properties of Al-Si alloy wire coating were investigated. The tensile strength and elongation of Al-Si alloy blank after annealing were tested. The metallographic structure of the finished Al-Si alloy wire after annealing was analyzed and characterized. The porosity, microhardness, bonding strength and thermal shock properties of the self-made Al-6Si wire and the imported Al-6Si wire(Metco SF Aluminum) were analyzed and compared. The results showed that the mechanical properties of Al-Si alloy billet were signifcantly improved by annealing at 450℃, and the grain of Al Si alloy wire was uniform after annealing at 400 ℃;The porosity, microhardness, bonding strength and thermal shock of the coating sprayed with self-made Al-6Si wire and imported Al-6Si wire were basically equivalent, which meet the application requirements of sealing coatings.