Volume 16, Issue 2 (March 1988)
A Microcomputer-Aided Four-Point Bend Test System for Determining Uniaxial Stress-Strain Curves
A microcomputer-aided four-point bend test system has been developed for determining the tensile and compressive stress-strain curves, as well as elastic constants, for a material from a single bend test. A special four-point bend fixture has been designed and constructed to minimize loading errors which may occur in the tests. Microcomputer software has been developed for processing the large amount of data obtained from each bend test. Two kinds of cast iron (ASTM A48 and A536), which exhibit different stress-strain characteristics in tension and compression, have been tested to examine the validity of the test system for a limited range of strain. It has been shown that the stress-strain relations derived from the bend tests are in good agreement with those obtained directly from the uniaxial tension and compression tests for strains less than about 5%. The advantages and limitations of the bend tests are also discussed.