| 摘要 |
PROBLEM TO BE SOLVED: To form an nonuniform layer structure in the process of forming a lamellar layer of coating, to improve its wearresistance and to reduce the production cost by using special aluminum-silicon thermal spraying powder generally free from copper. SOLUTION: As thermal spraying powder, two aluminum-silicon alloys generally free from copper (an A alloy and a B allay) are selected. The A alloy has the following compsn.: by weight, 23.0 to 40.0%, preferably about 25% Si, 0.8 to 2.0%, preferably about 1.2% Mg, <=0.6% Zr, <=0.25% Fe, and the balance aluminum. The ununiform lamillar structure of coating is composed of aluminum mixed crystals, silicon precipitates, intermetallic phases such as Mg Si and oxides, the average size of the silicon primary precipitates is <10 μm, and the average size of the oxides is <5 μm, the coating is generally free from copper, i.e., the ratio of copper is <1 wt.%, preferably <0.1 wt.%, and more preferably <0.01%. |
