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Q9. What are the differences between destructive and non-destructive testing methods for materials? Discuss the advantages and disadvantages of each approach and provide examples of specific tests used in both categories to ensure the integrity and quality of materials used in shipbuilding. (16)

Q8. (a) Explain Creep, Brinelling , Fretting and Fretting corrosion.

(b) Where and why does creep, Brinelling, Fretting and Fretting corrosion occur in a ship propulsion system?

Q3. (a) Define the term Torsional Vibration with respect to an engine crankshaft, stating the effect that high levels can have on an engine crankshaft. (6)

(b) Explain how engine deterioration influences the risk of Torsional Vibration, stating what can be done to minimise that risk. (5)

(c) Explain TWO possible reasons for the activation of a Torsional Vibration alarm after an engine has been started if there had been no previous history of such an alarm and if no maintenance had been undertaken on the engine whilst it was stopped. (5)

Q1. a) Describe the key phases and microstructures present in the iron-carbon equilibrium diagram and explain their significance in the heat treatment of steel. (8)

b) How do the different regions of the iron-carbon diagram influence the mechanical properties of steel, such as hardness, toughness, and ductility? Provide examples of how specific compositions and heat treatments can achieve desired properties. (8)

Q7. Discuss the causes of corrosion and the means by which corrosion of the following may be limited by manufacturers and ship’s personnel respectively:

A. Internal and External surfaces of auxiliary steam lines;

B. External surfaces of auxiliary boilers;

C. Water boxes of seawater coolers and condensers;

D. Main sea water inlet pipes.

Q6. Briefly describe the tests made on a piece of metal to determine its suitability for use in engineering. Explain clearly what is meant by any four of the following metallurgical terms:

(a) Work hardening,

(b) Cased hardening,

(c) Annealing,

(d) Normalising,

(e) Nitriding.

Q5. A. With reference to fatigue of engineering components explain the influence of stress level and cyclical frequency on expected operating life. (6)

B. Explain the influence of material defects on the safe operating life of an engineering component. (5)

C. State the factors which influence the possibility of fatigue cracking of a bed-plate transverse girder and explain how the risk of such cracking can be minimized. (5)

Q8. A. Explain the action of EACH of the following metallurgical mechanism:

(i) Creep;          (ii) Brinelling;   (iii) Fretting;     (iv) Fretting corrosion;

B .State, with reasons, where EACH of the mechanisms in occur in ship propulsion System.

Q7. With reference to steels used in shipbuilding and marine engineering:

(a) describe EACH of the following types of failure;

(i) Brittle failure;

(ii) Ductile failure.

(b) Explain the term ductile to brittle transition stating the factor that determines ductile to brittle transition.

(c) Describe a test to determine the value of brittle fracture of a specimen test piece.

Q6. A) Briefly state and describe the various heat treatment processes applied to cast iron main engine components. (4)

B) How do these treatments modify the microstructure and mechanical properties of the components? (6)

C) Provide examples of how heat treatment can improve wear resistance, strength, and service life in main engine parts. (6)

Q7. Compare the destructive testing done on engineering materials with non-destructive testing done on engineering components. Briefly describe one destructive test and two non-destructive tests to illustrate your answer

Q2. (a) Materials used for hull and machinery are subject to stress and strain in service.

Define EACH of the following:

(i) types of stress;              (ii) types of strain

(b) Describe the tests that may be carried out on steel to be used for ships side plating.(5)