The test results showed that the oxyacetyleneflame powder spray weld made the structure of the base material corse, or madethe tempering sorbite of the original steel become the corse pearlite and blockferrite decreasing greatly the hardness.

• 结果表明,火焰粉末喷焊使基体组织粗大,原淬火钢的回火索氏体,变成粗大的多相混合组织,硬度大大降低。