[Feb-2026] Pass API API-571 Exam in First Attempt Guaranteed! [Q80-Q104]

NO.80 Sigma phase occurs in Ferritic, martensitic, austenitic and duplex stainless steels when exposed to temperatures in the range of _____.

NO.81 Which of the following materials are generally not suitable for HF service?

NO.82 SSC is a form of ________ stress corrosion cracking.

NO.83 (In an RBI assessment, sulfidation was identified as a credible damage mechanism and assigned a corrosion rate of 8 mpy (0.20 mm/yr). Which of the following are critical factors in sulfidation?)

NO.84 Fatigue will not occur in carbon steel if stresses are below the:

NO.85 The effects of hydrogen embrittlement ___________ with _________ temperatures.

NO.86 Creep and stress rupture is more likely in a _________ grained material than a _______ grained material.

NO.87 Nitriding is usually confined to the surface of most components and will have a dull, ______ appearance. In more advanced stages, the material will exhibit very hard surface hardness.

NO.88 At high temperatures, metal components can slowly and continuously deform under load below the yield stress. This time dependent deformation of stressed components is known as __________.

NO.89 With ammonia stress corrosion cracking weld hardness should not exceed _______ BHN.

NO.90 _________ material sections also have a ___________ resistance to brittle fracture due to higher constraint, which increases triaxial stresses at the crack tip.

NO.91 Cracks connecting hydrogen blisters are referred to as ________.

NO.92 What standard refers to Fitness-For-Service evaluations?

NO.93 Exposure to high solution strength caustic can result in general corrosion or high corrosion rates above ________.

NO.94 If thermal shock damage may be present, which of the following should be checked?

NO.95 In most cases, brittle fracture occurs only at temperatures _________ the Charpy impact transition temperature.

NO.96 Which of these materials exhibit an endurance limit below which fatigue cracking will not occur?

NO.97 With sulfuric acid corrosion, mix points with _______ cause heat to be released and high corrosion rates can occur where the acid becomes diluted.

NO.98 Increasing the chromium in steels offers no major improvement in resistance to CO(2) corrosion until a minimum of __________ is reached.

NO.99 The major factors affecting high temperature sulfidation are the temperature, the presence of hydrogen, the H²S concentration and the ________.

NO.100 Key factors affecting thermal fatigue are the magnitude of the temperature and the __________.

NO.101 Caustic stress corrosion cracking typically propagates _______ to the weld in adjacent base metal but can occur in the weld deposit or heat affected zone.

NO.102 Which of the methods are effective for finding thermal fatigue cracks?

NO.103 In a naphthenic acid corrosive (NAC) environment, what is the effect of sulfur?

NO.104 Amine corrosion occurs principally on what class of materials?