Compared to standard silica bricks, semi-silica bricks feature _______________?
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Answer: C. Both A. and B.
Explanation
Semi-silica bricks incorporate additional clay into their mixture, which lowers their overall fusion point. The added clay component increases matrix plasticity, improving resistance to thermal shock and spalling. This balanced composition provides a practical compromise between refractoriness and thermal durability. Semi-silica refractories typically contain around eighty percent silica combined with plastic fire clays. Standard silica bricks are very pure but prone to thermal shock cracking during temperature swings. Clay additions modify the crystalline phase distribution during high temperature kiln firing processes.
Furnaces subject to fluctuating operational temperatures benefit from the enhanced spalling resistance of semi-silica. Selecting appropriate refractory grades prevents premature lining failure in cyclical industrial applications. Engineering materials for specific thermal regimes optimizes both performance and economic operating costs. Claiming only a reduced fusion point ignores the significant improvement in thermal spalling resistance. Stating only better spalling resistance overlooks the trade-off of a lower overall fusion point. Declaring neither property correct contradicts established refractory material science and testing data.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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