Stress relaxation in compression: A detailed discussion of the experimental method for ring test pieces

Following a careful study of the main sources of error in the Lucas test method for compression stress relaxation, improvements to the test procedure are suggested. In particular, a new method of loading the jigs is proposed which is easier and more reliable than those used previously. Slight modifications to standard jigs have overcome the problem of electrolytic corrosion by water and have enabled tests to be carried out in water for periods of up to two years.