Materials Testing & Quality Assurance Flashcards
7 cards from real ETC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Materials Testing & Quality Assurance flashcards as text
What does a Charpy impact test measure in a material?
Answer: Energy absorbed during fracture
The Charpy impact test measures the energy a notched specimen absorbs when struck by a swinging pendulum, indicating toughness.
In a Brinell hardness test, a 10 mm steel ball is pressed into a specimen. What is measured to calculate hardness?
Answer: Diameter of the residual indentation
Brinell hardness is calculated by dividing the applied load by the curved surface area of the indentation, using the measured indentation diameter.
Which destructive test method is used to determine a metal's yield strength, ultimate tensile strength, and elongation in one test?
Answer: Tensile test
A tensile test (tension test) generates a stress-strain curve that reveals yield strength, ultimate tensile strength, and percent elongation simultaneously.
A material exhibits a 0.2% offset yield strength. What does the 0.2% refer to?
Answer: The plastic strain offset used to define yield
The 0.2% offset method draws a line parallel to the elastic portion of the stress-strain curve starting at 0.2% strain to find yield strength for materials with no distinct yield point.
What is the primary purpose of a hydrostatic pressure test on a pressure vessel?
Answer: To verify structural integrity and check for leaks under pressure
A hydrostatic test fills the vessel with water and pressurizes it above operating pressure to confirm it can hold pressure without leaking or failing.
In quality control, what does AQL (Acceptable Quality Level) define?
Answer: The maximum defect rate considered acceptable for a lot
AQL specifies the worst acceptable process average defect rate; lots meeting this level are accepted with a specified probability during sampling inspection.
Which type of weld discontinuity does a guided bend test most effectively detect?
Answer: Lack of fusion and cracks
The guided bend test flexes a weld cross-section around a die, opening up internal lack-of-fusion defects and cracks that would not be visible on the surface.