Which one of the following is not a constituent of stainless steel ?

Stainless steel is a metal alloy primarily composed of iron, chromium, nickel, and carbon [3]. Chromium is the defining constituent, typically requiring a minimum of 10.5% to provide corrosion resistance by forming a protective oxide layer [t1][t2]. Nickel is added to enhance ductility, formability, and heat resistance [c2][t4]. Carbon, though kept in small amounts (usually less than 1.2%), is essential for increasing the hardness and strength of the alloy [c3][t5][t8]. Other common additives include manganese, molybdenum, and silicon [t1][t5]. Tin, however, is not a constituent of stainless steel; it is notably a component of bronze (an alloy of copper and tin) rather than steel alloys [c1]. Therefore, tin is the element among the options that does not belong to the standard composition of stainless steel.

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 8: Nature of Matter: Elements, Compounds, and Mixtures > A step further > p. 118
2. [3] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > 3.5.1 Prevention of Corrosion > p. 54