Accuracy of replication for non-destructive surface finish measurement

Surface replication has been widely used in aerospace, automotive and other industries as a non-destructive method for examination and assessment of either surfaces difficult to be accessed by measurement tools or parts difficult to be dismantled for measurement. The fidelity and accuracy of the replication is one of the major concerns in actual applications. This paper presents a comprehensive study of accuracy of replica materials for replicating and measuring surface roughness of engineering surfaces. In this study, three different replica materials, namely, Repliset, Technovit and Press-O-Film, have been used to replicate four ground surfaces with average roughness values ranging from 0.2 μm to 1.6μm. The original surfaces and their replicas were measured with tactile stylus profilometer and Alicona InfiniteFocus 3D optical microscope. Surface average roughness was calculated and compared between the original surfaces and their replicas. A discussion and suggestion on different replication techniques and materials used in surface roughness measurement are given.