Analysis of depth-sensing indentation tests with a Knoop indenter

The present work shows how data obtained in a depth-sensing indentation tes t using a Knoop indenter may be analyzed to provide elastic modulus and har dness of the specimen material, The method takes into account the elastic r ecovery along the direction of the short axis of the residual impression as the indenter is removed. If elastic recovery is not accounted for, the ela stic modulus and hardness are overestimated by an amount that depends on th e ratio of E/H of the specimen material. The new method of analysis express es the elastic recovery of the short diagonal of the residual impression in to an equivalent face angle for one side of the Knoop indenter. Conventiona l methods of analysis using this corrected angle provide results for modulu s and hardness that are consistent with those obtained with other types of indenters.