Improving the Life of 1070 Al Evaporator Tube Failed by the Pitting/Crevice Corrosion Based on Quantum/Transported Life-Stress and Sample Size

Abstract

To resolve the corrosion problem of a low-cost evaporator tube pitted in a household refrigerator, parametric accelerated life testing as a systematized strategy was applied. It included the following: (1) BX life with ALT way, (2) corrosion load modeling, (3) ALTs with revision, and (4) estimation whether the design attained the objective BX lifetime. A quantum/transported life-stress type and sample size were proposed. A case investigation was employed to enhance the lifetime of a household refrigerator whose evaporator tubing was failing corrosion. In the first ALT, this failure was reproduced by ALT equipment. The pitted tubing was determined to be identical to those returned from the marketplace. Using the scanning electron microscopy (SEM) with EDX, the trouble came from the chlorine concentration on tape. As action plans, they included: 1) changing the tape from PVC to polyethylene, 2) enlarging a contraction tube, and 3) attaching polyethylene foam. In the 2nd ALT, the lifetime of the refrigerator achieved a lifetime of B1 life 10 years.