Definition - What does Fractography mean?
Fractography is a quality control technique that was developed as early as the 16th century. This practice uses a microscope to analyze the failure chances of metals as well as plastics.
This process detects various failure modes common to both plastics and metals such as:
- Ductile overload
- Brittle fracture
- Chemical aging
- Residual stress
Corrosionpedia explains Fractography
Fractography was originally only applicable for the analysis of non-ferrous and ferrous metals. However, it can now be used with plastics as well.
The process was first recognized when it was successfully used in the detection of hydrogen embrittlement in steels. This greatly helped in photographing surface fractures in steels when the microscope is set at high magnifications.
Fractography was revolutionized in 1943 with the invention of the scanning electron microscope (SEM). This is more reliable because it is capable of expanding magnitude and enhancing the depth of focus.
The fractography process begins with gathering information and initial visual examination. Then, non-destructive testing follows, along with material characterization through thermal, mechanical and chemical testing. Next, the fracture surfaces are selected, preserved and cleaned prior to macroscopic and microscopic examination of the area.
When all these steps are completed, selecting and preparing cross sections follows, along with fracture or stress mechanism analysis.
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