What is the exact chemical composition ratio for Babbitt metal__________________?
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Answer: A. 87.75% Sn, 4% Cu, 8% Sb, 0.25% Bi
Explanation
Standard Babbitt metal formulations consist primarily of high tin percentages alloyed with antimony and copper elements. The exact chemical composition ratio of 87.75 percent tin, 4 percent copper, 8 percent antimony, and 0.25 percent bismuth provides optimal bearing performance. This precise balance forms hard micro-crystals embedded in a soft matrix, reducing friction in heavy machinery bearings. Babbitt metals are soft, low-friction alloy materials used extensively as bearing liners in rotating machinery. Antimony forms hard cuboid crystals that provide wear resistance, while tin and lead matrices offer conformability. Copper is added to increase the overall tensile strength and hardness of the molten bearing alloy.
Option B includes extra magnesium and inaccurate proportions that deviate from standard Babbitt alloy standards. Option C introduces aluminum instead of bismuth, altering the microstructural properties required for journal bearings. Option D specifies multiple non-standard additions that compromise the friction-reducing qualities of traditional Babbitt.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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