Revision

Important Alloys and Composition

A compact, tabular revision of common alloys, their constituent metals and their uses, for CAPF Paper I General Science (chemistry)

CAPF wiki2 min read4 sections
At a glance
SubjectGeneral Science
RevisionGeneral ScienceChemistryAlloysMetalsPaper 1

An alloy is a mixture of a metal with one or more other metals or non-metals, made to improve strength, hardness or corrosion resistance. Cover the right columns and recall the composition and use. CAPF tests alloy-to-composition matching. For element uses see elements and their uses.

Common alloys

Alloy Main composition Use
Brass Copper + Zinc Utensils, fittings, musical instruments
Bronze Copper + Tin Statues, coins, bells, bearings
Steel Iron + Carbon Construction, tools, machinery
Stainless steel Iron + Chromium + Nickel + Carbon Cutlery, utensils, surgical tools (rust-resistant)
Solder Lead + Tin Joining electrical wires and metal parts
Duralumin Aluminium + Copper + Magnesium + Manganese Aircraft bodies (light and strong)
Magnalium Aluminium + Magnesium Aircraft and lightweight parts
German silver Copper + Zinc + Nickel Utensils, ornaments (contains no silver)
Gun metal Copper + Tin + Zinc Gears, bearings, guns
Bell metal Copper + Tin (high tin) Bells, gongs
Type metal Lead + Tin + Antimony Printing type
Nichrome Nickel + Chromium Heating elements (high resistance)
Invar Iron + Nickel Instruments needing low thermal expansion
Pewter Tin + Copper + Antimony Decorative ware, tableware
Amalgam Mercury + another metal Dental fillings; gold extraction

Steel and special alloys

Alloy Note
Manganese steel Very hard; railway tracks, helmets, safes
Tungsten steel High-speed cutting tools
Nickel steel Cables, propeller shafts, axles
Chrome steel Cutting tools, crushing machinery
Stainless steel Corrosion-resistant; the chromium gives the rust resistance

Quick-recall facts

Fact Answer
Alloy of copper and zinc Brass
Alloy of copper and tin Bronze
Alloy used in aircraft (light) Duralumin / Magnalium
German silver contains Copper, zinc, nickel (no silver)
Alloy used as heating element Nichrome
Alloy that resists rust Stainless steel (chromium)
Alloy with mercury Amalgam

Cross-references

← BackAll of Revision