Which of the following tests is performed to measure the amount of elongation and the yield point of a metal?

Which of the following tests is performed to measure the amount of elongation and the yield point of a metal?

• A. Elongation Tests
• B. Rockwell Test
• C. Mass Spectrometer
• D. Tensile Test

Answer: (D)

Measuring how a metal deforms under load and when it starts to yield is revealed by a tensile test. In this test, a specimen is pulled from its ends while the force and the resulting elongation are recorded, giving a stress–strain curve. From that curve you can identify the yield point (where plastic, permanent deformation begins—often defined by a 0.2% offset method for materials without a sharp yield) and you can measure elongation as the percent change in gauge length at fracture. Elongation, a measure of ductility, is calculated as (final length − original length) / original length × 100. Other tests don’t provide both properties. A Rockwell hardness test measures hardness, not elongation or yield. A mass spectrometer analyzes composition, not mechanical behavior. An elongation test alone might quantify how much a sample elongates but doesn’t necessarily define the yield point. Therefore, the tensile test is the best choice for assessing both elongation and the yield point.

Measuring how a metal deforms under load and when it starts to yield is revealed by a tensile test. In this test, a specimen is pulled from its ends while the force and the resulting elongation are recorded, giving a stress–strain curve. From that curve you can identify the yield point (where plastic, permanent deformation begins—often defined by a 0.2% offset method for materials without a sharp yield) and you can measure elongation as the percent change in gauge length at fracture. Elongation, a measure of ductility, is calculated as (final length − original length) / original length × 100.

Other tests don’t provide both properties. A Rockwell hardness test measures hardness, not elongation or yield. A mass spectrometer analyzes composition, not mechanical behavior. An elongation test alone might quantify how much a sample elongates but doesn’t necessarily define the yield point. Therefore, the tensile test is the best choice for assessing both elongation and the yield point.