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根据理论假设和计算得出LY12CZ在3%NaCl水溶液中点蚀深度D_σ与外加应力σ及腐蚀时间t间符合等式D_σ=A×C_0exp(bσ)t~n=A′t~n,表明在腐蚀时间相同的情况下,点蚀深度与外加应力之间应符合Dσ=D_0exp(bσ)的指数函数规律;外加应力相同的条件下点蚀扩展速率与腐蚀时间符合D_σ=A′t~n的幂函数的规律。不同外加应力下的腐蚀浸泡实验证明,LY12CZ的点蚀深度D_σ扩展确实符合D_σ∝exp(bσ)t~n的规律。实验结果证明,铝合金的点蚀数据在有应力的条件下与无应力条件下具有相同的腐蚀深度-时间的幂函数规律,只是随应力大小的不同系数值有不同的变化,A值与外加应力间符合推导的A′=Aexp(bσ)指数函数规律。所以通过对A值进行修正可以将无应力下的自然腐蚀环境下的腐蚀数据推广到有外加应力的条件下使用。
According to the theoretical assumption and calculation, the pitting depth D_σ of LY12CZ in 3% NaCl solution agrees with the applied stress σ and corrosion time t, and the equation D_σ = A × C_0exp (bσ) t ~ n = A’t ~ n, When the corrosion time is the same, the relationship between the depth of pitting corrosion and the applied stress should be in accordance with the law of exponential function of Dσ = D_0exp (bσ). The growth rate of pitting corrosion and corrosion time under the same applied stress are in accordance with D_σ = A’t ~ n The law of power function. Corrosion immersion tests under different applied stresses show that the pitting depth D_σ of LY12CZ does accord with the law of D_σαexp (bσ) t ~ n. The experimental results show that the pitting corrosion data of aluminum alloy have the same law of power-law of corrosion depth-time under stress conditions and stress-free conditions, except that the values of different coefficients vary with the magnitude of stress. The stress is in accordance with the deduced A ’= Aexp (bσ) exponential function law. Therefore, by correcting the value of A, the corrosion data under natural stress-free environment can be generalized to the conditions under applied stress.