Chemical constituents commonly used in Chinese bronze medallion

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

Chemical composition of commonly used Japanese grade copper alloys

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

Chemical composition of commonly used German grade copper alloy

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

Comparison table of copper alloy grades

1、 Lead brass number comparison table

2、 Comparison table of common brass grades

3、 Comparison table of copper grades

Chemical composition of common copper alloy grades -- German grade

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

Chemical composition of common American copper alloy grades

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

Chemical composition of common copper alloy grades -- British grade

1、 Lead brass series

2、 Ordinary brass series

3、 Copper series

British standard chemical composition control table

Standard No.: bsg017-1981

European standard (en12164) chemical composition

         Note: cuzn36pb2as (cw602n) as arsenic content: 0.02-0.05; Mn content < 0.1.

Analysis of common defects of copper alloy tube bar profiles

    1. Overheating and over burning:

definition:

    In the process of heating or processing, due to the high temperature and long time, the structure and grain size of the island are called overheating. In case of severe overheating, the melting point between grains is never low, and the phenomenon of component melting or grain boundary weakening is called overburning.

Causes:

a. The heating temperature is high, the heating time is long or the heating time is long;

b. The end temperature of hot extrusion is too high or the residence time in high temperature region is long;

c. There are many low melting point components or impurities in the alloy.

2. Cracks or cracks:

definition:

    Continuous or intermittent irregular cracks appear on the surface of tube bar profile, slight crack is called crack, and severe crack is called crack.

Causes:

a. There are cracks, inclusions, shrinkage cavity, porosity, cold shut or other harmful impurities or crystal structure and chemical composition in the ingot;

b. Large stress exists in the ingot or the improper processing technology produces large stress;

c. The extrusion speed is too fast and the processing rate is too high;

d. Improper heat treatment process, processing or heat treatment in the brittle temperature region of the material.

3. Tail retraction:

definition:

    Shrinkage tail is a special defect of extruded product tail. At the end of extrusion, due to metal turbulence, oxide scale, lubricant and other dirt often flow into the ingot surface, resulting in metal delamination.

Causes:

a. The metal flow in the extrusion tail is disordered;

b. There are defects on the surface and sub surface of ingot, and pollutants such as lubricant in extrusion cylinder.

4. Bubbling

definition:

    After extrusion, drawing and return, the surface of the product is bulged along the processing direction. After dissection, it becomes a cavity. This kind of bulging is called bubbling. The bubbles are mostly strip-shaped with smooth surface and metallic luster inside. Some associated oxides or other inclusions are found.

Causes:

a. After extrusion, drawing and cold rolling, delamination is formed along the processing direction;

b. Excessive lubricant in extrusion barrel;

c. The shrinkage tail of extruded products is not cut off completely, and the delamination is formed after further stretching.

5. Dezincification

    definition:

    After annealing or acid pickling, the surface of zinc containing copper alloy tube and rod appears gray or reddish spots, which is called dezincification. The above spots appeared slightly and the microstructure changed after serious dezincification.

    Causes:

a. If the annealing temperature is too high, the flame will spray directly on the surface of the products, which will melt, volatilize or oxidize the zinc in the mark;

b. The extrusion temperature is too high;

c. During acid pickling, the concentration of acid solution is too high and the pickling time is too long, which leads to surface dezincification;

d. Under the action of environmental medium, chemical or electrochemical reaction occurs to form dezincification.

    6. Pockmarked noodles (commonly known as pitted spots and trachoma)

    definition:

    The surface of pipe rod type wire rod appears tiny point like depression, and the uneven rough surface is called pockmarked surface. Pockmarks are distributed locally, periodically or in patches. Some of them are called pockmarks, and the serious ones are called pockmarks.

    Causes:

a. High annealing temperature and long annealing time lead to coarse grains and serious dezincification;

b. Over pickling;

c. The machining rate is too small and the surface is not smooth;

d. The surface of processing equipment or tool is not smooth, and foreign matters are stuck and formed after contacting with materials.

    7. Ring mark on the surface

    definition:

    The surface or inner wall of pipe rod type wire rod has periodic circular bulge, which is called as the surface ring mark.

    The ring marks on the surface are produced in the processes of stretching, peeling and straightening. The ring marks are generally smooth, and the edges and corners of some convex edges are found. During the straightening process, a special ring bulge along 450 direction appears.

   Causes:

    a. The reason of drawing ring is that annealing temperature is not uniform, process and lubrication are poor, and pickling is not complete;

    b. The reason of peeling ring is that the design of peeling die is unreasonable and the drawing speed is not suitable; or the edge of peeling die is not sharp and the chip removal resistance is high;

    c. The cause of straightening ring is improper adjustment of roller angle or excessive pressure.

    Grades and uses of commonly used copper alloys

    There are 6 kinds of common brass

    1. H96, used for condenser tube, radiator, radiator and conductive parts.

    H80, used for thin-walled pipe, bellows, etc.

    H70, used for mechanical and electrical parts, etc.

    H68, used for complex cold stamping parts, deep drawing parts, radiator shell, etc.

    5. H65, used for hardware, small spring, screw and machine parts, etc.

    6. H62, used for rivets, pins, conduits, nuts, etc.

   There are 3 common brands of lead brass

    1. Hpb63-2, used for mechanical parts of general strength.

    2. Hpb61-1, used for high strength structural parts.

    3. HPb59-1, used for hot stamping and cutting parts, such as pins, screws, etc.

    There are 2 common brands of manganese brass

    Hmn58-2 and hmn57-3-1 are mainly used for parts used in corrosion conditions and weak current industry.

    There are 3 common brands of tin brass

    Hsn90-1, used for automobile, tractor elastic sleeve and other anti-corrosion friction reducing parts.

    High temperature corrosion resistant tubes, such as HSN2, hsn70, etc.

    3. HSn62-1, which is used for parts in contact with sea water and gasoline.

    There are 2 common brands of iron brass

    1. Hfe59-1-1, used for parts working under friction and corrosion, such as gasket, bushing, etc.

    2. Hfe58-1-1, used for hot pressing and cutting of high strength corrosion resistant parts.

    Nickel brass

    Hni65-5, used for pressure gauge tube, condensing tube and paper net, etc.

    There are 5 common brands of tin bronze

    1. Qsn4-3, corrosion and wear-resistant parts, diamagnetic components and springs, etc.

    Qsn4-4-2.5, parts bearing friction, such as shaft sleeve, bearing, disc, etc.

    Qsn6.5-0.1, spring contact plate, wear-resistant and antimagnetic parts in precision instruments.

    4. Qsn6.5-0.4, used for paper-making copper mesh, spring, wear-resistant parts, etc.

    5. Qsn7-0.2, used for the workpiece bearing friction, such as bearing worm gear and spring.

    There are 5 common brands of aluminum bronze

    1. Qai5, used for corrosion resistant elastic components.

    2. Qai9-2, pipe fittings working in steam below 250 ℃.

    Qai9-4, used for bearings, gears, valve seats, ship parts and electrical components.

    Qai7, used for gear, friction wheel, worm gear transmission mechanism, etc.

    Qai10-3-1.5, used for wear-resistant parts under high temperature, such as bearing, gear, flywheel, etc.

    There are 2 common brands of beryllium bronze

    Qbe1.7, used for important spring, sensitive element of precision instrument, etc.

 2. QBe2, used for important elastic components, bearings under high speed and high temperature working conditions.

    There are 2 common brands of silicon bronze

1. QSi1-3, used for friction parts working below 300 ℃, such as inlet and exhaust valve guide sleeve.

2. QSi3-1, used for spring, worm gear, worm gear and corrosion resistant parts.

Manganese bronze

    Qmn5 is commonly used to manufacture steam engine parts, various pipe joints of worm gear, steam valves and other high-temperature corrosion-resistant parts.

Disclaimer: some of the pictures and words in this website are collected and arranged on the Internet for study and exchange only. The copyright belongs to the original author, which does not represent my standpoint. This site will not bear any legal liability, if you have infringed upon your rights, please contact us in time to delete.

Disclaimer: Some pictures and texts on this site are collected from the Internet and are only for learning and communication. The copyright belongs to the original author and does not represent the views of our site. This site will not bear any legal responsibility. If your rights are violated, please contact us to delete it in time.