CRI Material Properties & Testing Standards 2

Question 1

Which ASTM standard governs reference radiographs for steel castings?

Accepted Answer

ASTM E186

Answer

ASTM E186 provides reference radiographs for heavy-walled (2–4.5 in.) steel castings.

Question 2

The ultimate tensile strength of a material is best described as:

Accepted Answer

The maximum stress a material can withstand before fracture

Answer

Ultimate tensile strength is the peak engineering stress on the stress-strain curve before fracture.

Question 3

Which material property describes resistance to localized plastic deformation caused by indentation?

Accepted Answer

Hardness

Answer

Hardness quantifies a material's resistance to permanent surface indentation or scratching.

Question 4

Laminar discontinuities in plate material are most parallel to which surface?

Accepted Answer

Rolled surface (plate face)

Answer

Laminations are elongated along the rolling direction and lie parallel to the plate face due to the rolling process.

Question 5

When radiographing austenitic stainless steel welds, grain noise is most problematic because:

Accepted Answer

Large grains scatter radiation, creating mottled images

Answer

Coarse austenitic grains scatter X-rays or gamma rays non-uniformly, producing a mottled or 'grass' background.

(CRI) Certified Radiographic Interpreter Practice Test