Meaning
Analytical technique used to determine the distribution of hardness values across a small surface area or cross section of a material. Microhardness mapping employs a diamond indenter to create a grid of microscopic impressions that are measured for size. This process identifies local variations in material strength that a standard bulk hardness test would miss.
Spatial Analysis
Visualization of the data often takes the form of a contour map where different colors represent varying levels of resistance to deformation. The microhardness mapping procedure reveals the depth of the case hardening layer or the presence of soft spots caused by improper cooling.
Quality Threshold
Manufacturers in the semiconductor and precision tool industries use these maps to certify that their products can withstand localized wear. If the microhardness mapping shows a significant drop in values near a welded joint, it indicates a heat affected zone that may be prone to cracking. The test is conducted according to international standards to ensure the results are comparable across different laboratories.
For high precision molds, the mapping must cover the entire working surface to guarantee uniform performance during the injection process.
Failure Mitigation
Analysis of returned or broken components often starts with this technique to locate the origin of the fault. By comparing the microhardness mapping of a failed part with a known good sample, engineers can determine if the issue was caused by a material defect or an operational overload.
