Laboratory Metallurgy & Metallurgist

Most engineers were not that involved in the science of metals around 1900, but the time 1950 arrived this field of study was very important to the engineer, for the engineer had to select material for the design, repair, or maintenance of the machine.

For the engineer understand the metal being examined, the engineer has to know what testing and evaluations are valid. Lets review this now:

Testing Technique - Obtaining significant results from field and laboratory equipment. Knowing their limitations and applicability.

Measurements - How much accuracy is required to achieve the result. An example is measuring 0.15% carbon content does not require accuracy out to 0.01500% since this amount has no significant effect on the low carbon steel properties. Another point is how many reading are necessary to obtain a useful average that provides significant results.

Evaluation of the Results - This is requires training, education and experience to evaluate the results of all the test results with macrographs and micrographs. The conclusion is presented in the final report in a condensed manner that is readily understood for application in the function and life of the machine or pressure part.

Some testing to consider:

• Visual - Macrographs and Micrographs

• Chemical Content of the metal

• Hardness measurement of the metal

• Tensile Strength with Yield Point

• Impact Testing

• Nondestructive Testing (NDT)

Good testing technique does not require state of the art equipment to give excellent relative results from the field or laboratory.  To evaluate requires training, education and experience and may only require a visual examination by a few macrographs or require micrographs, chemistry, impact testing, and nondestructive testing (NDT).

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