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GATE 2022 ME (ME1) – Question 29

Machine Design · Fatigue strength and S-N diagram · 1 mark · Multiple select

Which of the following methods can improve the fatigue strength of a circular mild steel (MS) shaft?

  1. Enhancing surface finish
  2. Shot peening of the shaft
  3. Increasing relative humidity
  4. Reducing relative humidity

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Show answer and explanation

Correct answer: (A) Enhancing surface finish; (B) Shot peening of the shaft; (D) Reducing relative humidity

Explanation

A smoother surface removes the places where cracks start. Shot peening puts the surface into residual compression. A humid environment encourages corrosion fatigue, so reducing the humidity helps and increasing it does not.