为研究涂层的热应力和应变与涂层结合强度之间的关系,对红外激光划痕后的涂层的热应力应变进行了理论分析,建立了涂层的热应力理论模型和应变公式。红外激光划痕涂层的试验结果表明,激光划痕后涂层在沿其厚度方向上的应变量有明显的突变过程,突变点的位置即是涂层从基体脱离下来的临界位置;激光划痕时涂层的剥离应力随涂层的温度增大而增大,并会呈现出两个阶段过程变化,进而说明了两个阶段之间的转折点反映了涂层结合强度的大小。
To research the relationship among the thermal stress , strain and interracial adhesion strength of coating. Thermal stress and strain of coating were theoretically analyzed, and theoretical model of coating's thermal-stress and strain formulas were established. The infrared-laser scratch testing indicates that there is an evident break process along the thickness of coating after it was scratched by infrared laser and the position of break point is the critical location where the coating is broken off from substrate. The research results also show that the separate stress of coating becomes stronger with the coating's temperature increasing when the coating is scratched by infrared laser. And the separate-stress presentes two phase process, which further illuminates that the turning point of two phase process reflects the interracial adhesion strength of coating.