Random Roughness Assessment by the Pin and Chain Method

Surface microrelief is frequently characterized using random roughness factors (RRF) defined by Allmaras et al. (1966). Random roughness factors are usually measured using a pin roughness meter or laser. Saleh (1993) recently proposed the chain method as a relatively simple, fast, and inexpensive technique for characterizing surface microrelief. The chain method is based on the principle that as a chain of given length is placed across a surface, the horizontal distance covered by the chain will decrease as surface roughness increases. Reductions in chain length caused by surface roughness are described as Saleh roughness factors (SRF).