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Consider the following statements: 1. The quenching of steel results in an increase in wear resistance, strength and hardness. 2. By the process of case hardening, hard wearing resistant surface is produced on mild steel. This is an effective method for low carbon steels because they cannot be hardened by the process of quenching. 3. When a metal is mixed with small atoms of non-metallic element in such a manner that invading atoms occupy interstitial positions in the metal lattice, an interstitial alloy results. What of the above statements are correct?

Consider the following statements: 1. The quenching of steel results in an increase in wear resistance, strength and hardness. 2. By the process of case hardening, hard wearing resistant surface is produced on mild steel. This is an effective method for low carbon steels because they cannot be hardened by the process of quenching. 3. When a metal is mixed with small atoms of non-metallic element in such a manner that invading atoms occupy interstitial positions in the metal lattice, an interstitial alloy results. What of the above statements are correct? Correct Answer 1, 2 and 3

Quenching of steel results in martensite formation which is very hard and strong, increase in hardness, wear resistance and strength.

Case hardening is the method of enhancing surface wear resistance by providing thermochemical treatments that includes carburizing, nitriding, and carbonitiding. Case hardening is an effective method for low C-steel because they have not enough carbon to be hardened by quenching, whereas by case hardening it produces hard and wear resistant surface over a strong, tough core.

Interstitial solid solution are formed when the atomic radius of the solute atom is smaller than the parent metal atom.

Related Questions

Four couples go to a party. All the women are wearing different colour sarees. All men are wearing different coloured shirts. The colour of a shirt and a saree can be the same. Consider all the statements given below and answer the questions. Statement: 1. Rama is married to Ramesh who is wearing a red shirt. 2. Purva, who is not Anup's wife, is wearing a blue sari. 3. Anup and Shreya are wearing green clothes. 4. Sandesh's wife Mrunmayi has not worn a yellow sari. 5. Viraj is wearing a yellow shirt. Question: Who is Shreya's husband?
Consider the following statements: 1. HSS tools wear very rapidly, whereas in cemented carbide tools, even though hardness is retained, crater wear can occur due to solid-state diffusion. 2. Cutting tools made of Super-HSS, also known as cobalt-based HSS, are made by adding 2% to 15% of cobalt which increases the cutting efficiency at heavier cuts by increasing the hot hardness and wear resistance. 3. Tools failure due to excessive stress can be minimized by providing small or negative rake angles on brittle tool materials, protecting tool tip by providing large side-cutting edge angles, and honing a narrow chamfer along the cutting edge. Which of the above statements are correct?
Consider the following statements regarding crystal defects: 1. In metals, a self-interstitial introduces relatively large distortions in the surrounding lattice because the atom is substantially larger than the interstitial position in which it is situated. 2. All crystalline solids do not contain vacancies and, it is possible to create such a material that is free of these defects. 3. Impurity point defects are found in solid solutions, of which there are two types: Substitutional and interstitial.  Which of the above statements is/are correct?
An alloy A contains two elements, copper and tin in the ratio of 2 : 3, whereas an alloy B contains the same elements in the ratio of 3 : 4. If 20 kg of alloy A, 28 kg of alloy B and some more pure copper are mixed to form a third alloy C which now contains copper and tin in the ratio of 6 : 7, then what is the quantity of the pure copper mixed in the alloy C?
An alloy A contains two elements, copper and tin in the ratio of 2 ∶ 3, whereas an alloy B contains the same elements in the ratio of 3 ∶ 4. If 20 kg of alloy A, 28 kg of alloy B and some more pure copper are mixed to form a third alloy C which now contains copper and tin in the ratio of 6 ∶ 7, then what is the quantity of the pure copper mixed in the alloy C?
Consider the following statements
1. Galvanisation is the method of protecting steel and iron fromrusting by coating them with a thin layer of zinc.
2. Pure iron is very soft but if it is mixed with a small amount of carbon, it becomes hard and strong.
3. When iron is mixed with nickel and chromium, we get stainless steel, which is hard and does not rust.
Which of the statements given above are correct?
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The only suitable method for hardening the low carbon steel is case hardening. Which of the following is a case hardening process?
Three persons P,Q and R wore shirts of White, Black and Blue colours (not necessarily in that order) and pants of Green, Red and Whitecolours (not necessarily in that order). No persons wore shirts and pants of same colour. And further it is given that 1.A did not wear shirt of Black colour.
2.B did not wear shirt of Blue colour.
3.C did not wear shirt of White colour.
4.A did not wear pants of Green colour.
5.B wear pant of White colour. What were the colours of the pant and shirt wear by person A respectively?
The recrystallization behaviour of a particular metal alloy is specified in terms of recrystallization temperature, which is typically 1/3rd of the absolute melting temperature of a metal or an alloy and depends on several factors including the amount of 1. cold working and purity of the metal and alloy 2. hot working and purity of the metal and alloy Which of the above is/are correct?