Manganese is probably the most versatile element which can be added to
copper alloys. Small additions of manganese (0.1 to 0.3%) are used to deoxidise
the alloy and improve its castability and mechanical strength. Manganese has a
high solid solubility in copper and in binary systems with copper and
aluminium, zinc or nickel as the binary constituent. Many commercial copper
alloys contain around l to 2% manganese to improve strength and hot
workability. In order to reduce costs, manganese can replace part of the nickel
in nickel-silver alloys.
Far higher levels of manganese content are found in some alloys for
specific applications. Although most have levels of 10 to 20% there are some
alloys with >50% Manganese content. These are produced in small quantities
for such specific properties as damping capacity or high-thermal expansion
coefficient. One such alloy, 72% Mn, 18% Cu, 10% Ni, is used for bimetallic
strips in temperature control devices fitted to cars and other vehicles.
Another alloy, sold under the commercial name "Manifor" is a non-magnetic
high-strength alloy (60% Cu, 20% Mn, 20% Ni), used to manufacture small parts
for the watchmaking industry. However, copper alloys represent only two million
tons per year and hence comprise only a limited market for manganese.