Here are some suggestions for successful microhardness testing, including some common errors that often occur.

Our discussion of hardness testing now focuses on microhardness testing methods.

We continue our discussion of hardness testing by focusing on Rockwell testing.

We continue our discussion of hardness testing by focusing on Brinell testing.

For the most accurate hardness measurements, proper alignment of the indenter to the sample surface is critical.

Hardness testing is the most common quality-control checks performed in the heat-treat shop.

Hardenability is the ability of steel to partially or completely transform from austenite to some fraction of martensite at a given depth below the surface when cooled under a certain condition. The “gold standard” test for all hardenability results has always been the “Jominy End-Quench Test.” 

The Jominy, or end-quench test, determines the capacity of steel to harden under defined heating and cooling parameters. ASTM A255 (Standard Test Methods for Determining Hardenability of Steels) provides the guidelines/procedures for performing the Jominy test.