Case depth determination in heat-treated industrial steel products using photothermal radiometric interferometric phase minima.
Case depth determination is a quantitative calibrated methodology based on photothermal radiometric (PTR) depth-profilometry for non-contact, non-intrusive determination of effective case depth in heat-treated case-hardened steel products was developed.

Several types of heat-treated C1018 industrial steel screw products (with hexagonal, cylindrical and spherical heads) are statistically evaluated using the case-depth-induced interferometric thermal-wave phase minima.

Calibration curves for each type of sample are established with the help of conventional destructive indenter measurements. It is shown that PTR thermal-wave interferometric phase minima can be used as a fast, on-line inspection methodology of industrial steel products for non-destructive quality and feedback control of heat-treating processes.

LMATS is NATA accredited to perform case depth measurement in accordance with AS 1982

• Method 6.1: Hardness traverse
• Method 6.2: Micrographic test
• Method 6.3: Macroscopic test

LMATS can perform cased depth measurement in accordance with AS 1982

• Method 6.4: Micro hardness test
• Method 6.5: Chemical test
• Method 6.6: Spectrometric test

Methods 6.1 to 6.3 are cost effective methods and Methods 6.4 to 6.6 are relatively expensive methods.