By John Paschkewitz
HALT training and application has focused primarily on electronic products. But, HALT is a methodology, and the basics can be applied to any product and stress. The basic approach to HALT is to apply a single stress in a stepwise manner until an operational limit or destruct limit is reached to find the strength margin of the product relative to that stress. Similarly, other stresses identified can be applied one at a time to find limits. Once the limits are found, an accelerated profile can be determined and the product is then cycled to reveal weaknesses in the design that can be corrected. For electronics, temperature, repetitive shock vibration, and power variation or on/off cycling are typical stresses applied in HALT.
To apply the HALT methodology to non-electronic products, we need to begin with an understanding of the stresses applied to the product and the potential failure mechanisms precipitated. Analysis of the design and application with tools like Failure Modes and Effects Analysis, Finite Element Analysis, or similar approaches help identify the stresses to use in testing the product, component, or assembly. A basic Physics of Failure approach is needed. Both overstress and cumulative damage wear out mechanisms will be discussed. This webinar will look at applying this approach to some electrical and mechanical products to illustrate how the HALT method can help improve the design and reliability of products other than electronics. Although less work has been done to use HALT in these products, there is considerable benefit to applying the HALT methodology