RESEARCH STATUS AND PROSPECTS FOR SMALL PUNCH TESTING TECHNIQUE

The Small PunchTesting technique (SPT) is an innovative technique which haspotentials for residual life and structural integrity assessmentof components in service. The sample for small punch test needsonly a modest amount of material from the component surface. Ithas been used to determine the materials' elastic modulus, yieldstress, ultimate, ductile-brittle transition temperature, fracturetoughness, creep properties, edurance strength et al. Then thetesting results can be used to evaluate the residual life andintegrity of structure in service. The test itself is rathersimple to perform with no repair after sampling. Since early1980's, the technique has been developed and applied to nuclearreactors and electric power plants for safety assessment. Thetechnical standards are issued or being set up in United States,Europe and Japan. The objective of this paper is to provide anoverview of the test technique, and give suggestions how to applythis technique to engineering practice and build up technicalstandard in China.