Which hardness test fails to measure indentation hardness in metals and alloys?
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Answer: B. Shore scleroscope test
Explanation
The Shore scleroscope measures the elastic rebound height of a small diamond tipped hammer dropped onto the metal. This rebound metric quantifies elastic resilience and hardness based on dynamic energy restitution rather than indentation. Unlike standard indentation tests it does not measure permanent plastic deformation surface impressions. Indentation hardness tests measure the permanent depth or surface area of an impression left by a penetrator. Brinell Vickers and Rockwell tests apply static loads using hardened steel balls or diamond indenters. Dynamic hardness testers evaluate the rebound velocity of an impacting mass on metallic test specimens.
Option A Vickers hardness test uses a square based diamond pyramid indenter to measure permanent surface impressions. Option B is the correct answer because it measures rebound height rather than physical indentation dimensions. Option C Brinell hardness test forces a hardened carbide ball into the metal to measure permanent indentation diameter.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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