Home » Mechanical Engineering » Machine Design

Effect of heating on toughness (impact energy capacity) When a metallic material is heated, how does its toughness generally change? Choose the correct trend.

Difficulty: Easy

Increases
Decreases
Remains unchanged
First increases, then decreases

Correct Answer: Increases

Explanation:

Concept
Toughness reflects the ability to absorb energy before fracture (area under the stress–strain curve). For most ductile metals, increasing temperature reduces brittleness and increases ductility, so impact energy and toughness rise with heating (within typical service ranges).

Final Answer
Increases

← Previous Question Next Question→

More Questions from Machine Design

Flange coupling: method of joining the two flanges Identify how the mating flanges in a standard rigid flange coupling are secured together. Choose the correct option.
Relative ductility comparison among common engineering metals Which listed material exhibits the highest ductility (greatest uniform elongation before fracture)? Choose the correct option.
Riveted joints: Unwin's formula for rivet diameter vs. plate thickness Let t (mm) be the plate thickness. According to Unwin's empirical relation, select the correct expression for rivet hole diameter d (mm). Choose the correct option.
Examples of class-III (third-type) levers Identify the device that operates as a third-type lever (effort between fulcrum and load). Choose the correct example.
Torsion: solid vs. hollow shaft with identical length, weight, and material Two shafts A (solid) and B (hollow) have the same length, weight, and material; both are under pure torsion. State the correct comparative statement about their torsional strength/stiffness.
Preferred numbers (Renard series): constant factor for the R10 series In engineering standardization, the Renard R10 series uses a constant ratio between successive preferred numbers. What is the constant factor (common ratio) for the R10 series?
Sleeve (muff) coupling: design idealization for torsion When analyzing a sleeve/muff coupling for power transmission, the sleeve is modeled as which type of torsional member? Choose the best option.
Flanged pipe joint: bolt circumferential pitch for a leak-proof joint For a flanged pipe joint, what range of circumferential pitch (bolt spacing along the circle), in terms of the bolt-hole diameter d, helps ensure a leak-proof joint? Choose the correct range.
Fatigue design: basis of the Soderberg relation In fatigue/dynamic loading design, the Soderberg line uses which material property on the static-stress axis (unlike other relations that often use ultimate strength)? Choose the correct property.
Power screws: condition for an overhauling screw A screw is said to be ‘‘overhauling’’ when the load tends to lower itself without external effort. Which efficiency range corresponds to this condition?

Discussion & Comments

No comments yet. Be the first to comment!

Join Discussion