Chromel, also known as Nichrome, consists of an alloy of_____________________?
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Answer: B. Nickel and chromium
Explanation
Chromel, widely known by the trademarked name Nichrome in various applications, is a metallic alloy. It is formulated primarily by combining nickel and chromium in specific metallurgical proportions. This precise alloy composition provides high electrical resistance and excellent oxidation resistance. Resistance heating alloys must withstand high temperatures without forming flaking oxide scales. Nickel-chromium alloys typically consist of approximately 80 percent nickel and 20 percent chromium. Thermocouple alloys like chromel-alumel generate measurable thermoelectric voltages across temperature gradients.
Electric furnaces and household heating appliances utilize Nichrome wire heating elements extensively. Industrial temperature measurement relies on chromel wire as a standard positive thermocouple leg. Corrosion resistance in high-temperature air makes these alloys indispensable for thermal equipment. Molybdenum is used in high-temperature vacuum furnaces rather than standard chromel alloy formulations. Option B correctly identifies nickel and chromium as the primary constituents of chromel alloys. Chromium and aluminum are combined with iron in other specialized resistance heating alloys like Kanthal.
- Subject
- Engineering
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- Chemical Engineering
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