Figure 7
From: In-situ Monitoring on Micro-hardness of Laser Molten Zone on AISI4140 Steel by Spectral Analysis

The correlation among dimensionless micro-hardness, dimensionless intensity of spectra lines and dimensionless energy density (a) dimensionless micro-hardness of molten zone and dimensionless energy density (b) dimensionless intensity of spectral lines and dimensionless energy density.