Evaluation of high-temperature Vickers hardness using instrumented indentation system

Instrumented indentation testing is more advanced than conventional hardness testing in measuring various mechanical properties of materials. To evaluate these mechanical properties, information about indentation contact area is required. In particular, the deformation behavior of metals at high-temperatures seems to differ from that at room temperature, and thus for accurate evaluation of mechanical characteristics at high-temperatures, the high-temperature contact area should be used. In this study, an instrumented indentation system for high-temperatures was developed and measurement-errors caused by equipment temperature were calibrated. In addition, the pileup effect during indentation was studied at different temperatures. A new equation for the high-temperature contact area is proposed. For verification, conventional hardness testing was performed to compare the results with high-temperature instrumented indentation testing.