ASTM A892 – Standard Guide for Defining and Rating the Microstructure of High Carbon Bearing Steels
This guide covers the definition and rating of the microstructure of carbide structures in annealed high carbon bearing steels. Requirements for the optical metallograph apparatus and specimen preparation including polishing and etching are detailed. The description of the reference photomicrographs (graded illustrations of annealed carbides categorized by size, network, and lamellar content (shape)) that shall be used in the evaluation and the equation that shall define the rating are given.
1.1 This guide covers the description of carbide structures in annealed high carbon bearing steels.
1.2 Included is a guide for rating steel specimens by a graded series of photomicrographs showing the incidence of certain conditions.
1.3 The reference photomicrographs are graded illustrations of annealed carbides categorized by size, network, and lamellar content (shape).
1.4 This guide is to facilitate communication and description of microstructure. It does not establish limits of acceptability. Such limits are a matter of agreement between user and producer.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.