Definition of surface roughness of forgings
The surface roughness of forgings refers to the micro-geometrical shape features of small spacing and peak valleys on the machined surface. The ratio of wavelength to wave height is generally less than 50.
Evaluation parameters for surface roughness of forgings
The evaluation parameters relating to the height characteristics stipulated in the national standard are as follows.
① contour arithmetic mean deviation RA, within the sampling length L, the arithmetic mean of the absolute value of the median offset from each point to the contour of the measured contour.
② Contour Uneven Cross height RZ brother in the sample length L, the sum of the average of 5 maximum contour peaks with 5 maximum contour valleys depth.
③ Contour Maximum height ry the distance between the maximum contour peak line and the lowest contour line in the sample length L.