【Daily Topic】【HVAC Version 20160923】
Thread Content
Participation reward: 2 Wealth. Reward for correct answer: 9 Wealth. Which of the elements such as carbon, silicon, manganese, sulfur, and phosphorus contained in steel have an impact on the properties of steel? ( ) A. When the carbon content exceeds 1.00%, the strength of steel decreases; it becomes more ductile, has lower hardness, and is easier to process. B. High levels of sulfur and phosphorus can cause heat brittleness and cold brittleness in steel, but they have little effect on its ductility and toughness. C. Silicon and manganese can increase the strength and hardness of steel without significantly reducing its ductility and toughness. D. Manganese can increase the strength and hardness of steel, while silicon significantly reduces its ductility and toughness. Correct answer: C
C. Silicon and manganese can increase the strength and hardness of steel without significantly reducing its plasticity and toughness
C. The carbon content in A is around 0.25%; an increase in carbon can inhibit intergranular corrosion, and 304 has greater corrosion resistance than 316L. Among them, both the sulfur element in B and phosphorus are harmful elements that should be reduced. Manganese enhances magnetism; the manganese content in special steels is very low, such as in the plates used on aircraft carrier decks. The role of Si is unclear. Mo is mainly used on metal surfaces to enhance corrosion resistance. One thing that’s not clear is that various types of sheets are originally made from channel steel, that is, high-carbon steel, which is then processed into different types of sheets. Is it this process?
C、、、、、、、、、、、、、、、
D. Manganese can increase the strength and hardness of steel, while silicon significantly reduces its plasticity and toughness
The correct option regarding the influence of elements such as carbon, silicon, manganese, sulfur, and phosphorus contained in steel on its properties is (D). A. When the carbon content exceeds 1.00%, the strength of the steel decreases; it has high plasticity, low hardness, and is easy to process. B. High levels of sulfur and phosphorus can cause hot brittleness and cold brittleness in steel, but they have little effect on its plasticity and toughness. C. Silicon and manganese can increase the strength and hardness of steel without significantly reducing its plasticity and toughness. D. Manganese can enhance the strength and hardness of steel, while silicon significantly reduces its plasticity and toughness