Basic Knowledge of Brass (Part Three)

Jan 30, 2018

Tin Brass
Adding tin to brass can significantly improve heat resistance of the alloy, which can especially improve resistance of the alloy to sea water. Therefore, tin brass can also be called admiralty brass.

Tin can dissolve in the copper-based solid solution, playing a role of strengthening the solid solution. However, with the increasing tin content, the brittle r phase (the CuZnSn compound) appears in the alloy, which is not good for plastic deformation of the alloy. Thus, the tin content in tin brass is usually between 0.5% and 1.5%. The commonly used tin brass include HSn70-1, HSn62-1 and HSn60-1. HSn70-1 is α alloy, which has high plasticity. It can be processed by cold or hot press working. The other two alloys have the α plus β two-phase structure, and a small number of r phases often appear. The other two alloys have low plasticity at room temperature, and they can only be deformed in the hot state.

Manganese Brass
Manganese has greater solubility in the solid brass. Adding 1% to 4% manganese to brass can significantly improve strength and corrosion resistance of the alloy without reducing its plasticity. Manganese brass has the α plus β structure. Manganese brass has pretty good processability in the cold and hot state.

Iron Brass
Iron precipitates as the particle of the iron-rich phase in the iron brass. Iron as the crystal nucleus can refine grains and prevent recrystallized grains from growing so as to improve mechanical properties and processing properties of the alloy. The iron content in iron brass is usually below 1.5%, and iron brass has the α plus β structure, which make iron brass have good strength and toughness, good plasticity at high temperature and deformation also in the cold state. The common grade is the Hfe59-1-1.

Nickel Brass
Nickel and copper can form a continuous solid solution, which can significantly expand the α region. Adding nickel to brass can significantly improve corrosion resistance of brass in the atmosphere and seawater. Nickel can also increase recrystallization temperature of brass and facilitate the formation of smaller grains. HNi65-5 nickel brass has a single phase α structure, which makes nickel brass have good plasticity at room temperature and be deformed in the hot state. However, the content of lead impurities must be strictly controlled, or it will seriously deteriorate the thermal processing properties of the alloy.

Different Grades for Brass in Different Countries

China GB	Germany DIN		Europe EN		International Standard ISO	The United States UNS	Japan JIS
H96	CuZn5	2.022	CuZn5	CW500L	CuZn5	C21000	C2100
H90	CuZn10	2.023	CuZn10	CW501L	CuZn10	C22000	C2200
H85	CuZn15	2.024	CuZn15	CW502L	CuZn15	C23000	C2300
H80	CuZn20	2.025	CuZn20	CW503L	CuZn20	C24000	C2400
H70	CuZn30	2.0265	CuZn30	CW505L	CuZn30	C26000	C2600
H68	CuZn33	2.028	CuZn33	CW506L	CuZn35	C26800	C2680
H65	CuZn36	2.0335	CuZn36	CW507L	CuZn35	C27000	C2700
H63	CuZn37	2.0321	CuZn37	CW508L	CuZn37	C27200	C2720
HPb63-3	CuZn36Pb1.5	2.0331	CuZn35Pb1	CW600N	CuZn35Pb1	C34000	C3501
HPb63-3	CuZn36Pb1.5	2.0331	CuZn35Pb2	CW601N	CuZn34Pb2	C34200	－
H62	CuZn40	2.036	CuZn40	CW509N	CuZn40	C28000	C3712
H60	CuZn38Pb1.5	2.0371	CuZn38Pb2	CW608N	CuZn37Pb2	C35000	－
HPb63-3	CuZn36Pb3	2.0375	CuZn36Pb3	CW603N	CuZn36Pb3	C36000	C3601
HPb59-1	CuZn39Pb2	2.038	CuZn39Pb2	CW612N	CuZn38Pb2	C37700	C3771
HPb58-2.5	CuZn39Pb3	2.0401	CuZn39Pb3	CW614N	CuZn39Pb3	C38500	C3603
－	CuZn40Pb2	2.0402	CuZn40Pb2	CW617N	CuZn40Pb2	C38000	C3771
－	CuZn28Sn1	2.047	CuZn28Sn1As	CW706R	CuZn28Sn1	C68800	C4430
－	CuZn31Si1	2.049	CuZn31Si1	CW708R	CuZn31Si1	C44300	－
－	CuZn20Al2	2.046	CuZn20Al2	CW702R	CuZn20Al2	C68700	C6870

Chemical Composition

China	Japan	Germany	The United States	UK
H62	C2720	CuZn40	C27400	CZ109
H65	C2680	CuZn35	C27000	CZ107
H68	C2600	CuZn30	C26000	CZ106

Japanese Grades

Grade	Main composition		The content of the impurities %			Total impurities %	The corresponding Chinese grade
Grade	Cu	Zn	Pb	Fe	Ni	Total impurities %	The corresponding Chinese grade
C2720	62-64	Balance	≤0.07	≤0.07	--	--	HP62
C2700	63-67	Balance	≤0.05	≤0.05	--	--	H65
C2680	64-68	Balance	≤0.05	≤0.05	Bi≤0.002	Sb≤0.005	H68
C2600	68.5-71.5	Balance	≤0.05	≤0.05	--	--	H70

American Grades

Grade	Main composition		The content of the impurities %			Total impurities %	The corresponding Chinese grade
Grade	Cu	Zn	Pb	Fe	Ni	Total impurities %	The corresponding Chinese grade
C27400	61-64	Balance	≤0.10	≤0.05	--	--	HP62
C27000	63-68.5	Balance	≤0.10	≤0.07	--	--	H65
C26000	68.5-71.5	Balance	≤0.07	≤0.05	--	--	H68, H70