Gold Gold Copper Silver 24 karat gold 18 karat gold 14 karat gold 24/24atoms Au 18/24atoms Au 14/24atoms Au
Solid Brass • An alloy is a mixture of metals. • Brass = Copper + Zinc • Solid brass • homogeneous mixture • a substitutional alloy Copper Zinc
Brass = Copper + Zinc • Brass plated • heterogeneous mixture • Only brass on outside Brass Plated Copper Zinc
Hardened Steel a interstitial alloy Steel Iron Carbon
Tensile strength Force is added Steel Alloys • Stainless steel • Tungsten hardened steel • Vanadium steel • We can engineer properties • Add carbon to increase strength • Too much carbon too brittle and snaps • Too little carbon too ductile and iron bends
Galvanized Nails and Screws • Zinc coating prevents rust • Use deck screws for any outdoor project • Iron will rust if untreated • Weaken and break
Nitinol Wire • Alloy of nickel and titanium • Remembers shape when heated Applications: surgery, shirts that do not need to be ironed.
Properties of Matter • Electrical Conductivity • Heat Conductivity • Density • Melting Point • Boiling Point • Malleability • Ductility