Copper castings, as an important metal material, have a long history and wide applications. With the advancement of technology and the development of industry, the production process, performance characteristics, and application fields of copper castings are constantly expanding and improving. In the future, copper castings will continue to develop towards high performance, precision, greenness, intelligence, and multifunctionality, making greater contributions to the development of modern industry and society.

The quality control of copper castings is the key to ensuring their performance and service life. The main control measures include. Raw material control: Strictly select qualified copper alloy raw materials to ensure that their chemical composition and physical properties meet the requirements. Process control: Optimize casting process parameters, such as pouring temperature, cooling rate, etc., to reduce casting defects. Inspection control: Comprehensive inspection of castings is carried out using non-destructive testing, metallographic analysis, and other methods to ensure that their quality meets standards.

What problems may occur during the use of copper castings?

Corrosion issue

Chemical corrosion: Copper will undergo chemical reactions with surrounding chemicals under certain conditions, such as in media containing acids, bases, and salts. Copper atoms on the surface of copper castings may lose electrons, forming copper ions that enter the solution and cause corrosion of the castings. For example, in chemical production, copper valves, pipelines, and other components that come into contact with acidic media such as sulfuric acid and hydrochloric acid are prone to chemical corrosion.

Electrochemical corrosion: When copper castings come into contact with other metals or conductive media, a galvanic cell is formed due to the potential difference between different metals, leading to electrochemical corrosion of copper castings. In a humid environment, when copper castings are connected to metals such as steel, copper acts as the positive electrode and iron acts as the negative electrode, causing corrosion and accelerating the damage of copper castings.

Stress corrosion cracking: When copper castings are subjected to tensile stress while also being in a specific corrosive environment, stress corrosion cracking may occur. For example, in some high-temperature and high-pressure environments, copper pipelines or containers are prone to stress corrosion cracking and safety issues such as leakage if they come into contact with specific media such as ammonia under the tensile stress generated by internal pressure.

Wear and tear issues

Abrasive wear: When copper castings come into contact with other objects and move relative to each other, if there are hard particles such as dust, sand, etc. between the contact surfaces, these particles will cut and scrape the surface of the copper castings like abrasives, causing the surface material to gradually wear down. For example, in some mining machinery, copper gears, bearings, and other components work in harsh environments containing a large amount of dust, making them prone to abrasive wear.

Adhesive wear: On the surface of copper castings in relative motion, due to excessive local pressure, adhesion occurs between the micro protrusions on the surface. As the relative motion continues, the adhesive points are sheared, causing the material to transfer from one surface to another, resulting in adhesive wear. In high-speed rotating copper bearings, poor lubrication between the shaft and bearings can easily lead to adhesive wear, affecting the normal operation of the equipment.

deformation

Hot deformation: During the use of copper castings, if they undergo drastic temperature changes or are exposed to high temperatures for a long time, due to the large coefficient of thermal expansion of copper, significant thermal stress will be generated. When the thermal stress exceeds the yield strength of the material, it will cause deformation of the casting. For example, in some heat treatment equipment, copper fixtures, molds, and other components are prone to thermal deformation during heating and cooling, which can affect their dimensional accuracy and performance.

Mechanical deformation: When copper castings are subjected to excessive external forces, such as in mechanical transmission, copper gears, worm gears, and other components may undergo elastic deformation or even plastic deformation if the load exceeds their carrying capacity during power transmission, affecting transmission accuracy and equipment stability.

Fatigue problem

High cycle fatigue: Under the action of alternating loads, fatigue cracks will appear on the surface or inside of copper castings. As the number of load cycles increases, the cracks gradually expand, ultimately leading to the fracture of the casting. For example, in some vibration equipment, copper springs, connecting rods, and other components are subjected to periodic vibration loads for a long time and are prone to high cycle fatigue failure.

Low cycle fatigue: When copper castings are subjected to high alternating stress but with relatively few cycles, low cycle fatigue failure can also occur. This situation usually occurs in equipment that is subjected to impact loads or frequently starts and stops, such as copper pistons in car engines.

Pores and shrinkage issues

Problems caused by internal porosity and shrinkage porosity: Internal porosity and shrinkage porosity formed during the casting process can reduce the density and strength of copper castings. During use, these defects may become sources of stress concentration, accelerate the generation and propagation of cracks, and lead to premature failure of castings. For example, in copper pipes and containers under pressure, pores and shrinkage may cause leaks, affecting the safety and reliability of the equipment.

Copper is an excellent conductive and heat-conducting material, widely used in electrical and electronic fields such as wires, cables, heat sinks, etc. Copper and its alloys have good corrosion resistance in air, water, and many chemical media, making them suitable for harsh environments such as chemical and marine engineering. Copper castings have high strength and hardness, as well as good plasticity and toughness, and can withstand large loads and impacts.

The commonly used materials for copper castings include pure copper, brass, bronze, and white copper. Copper castings made of different materials have different performance characteristics: pure copper has good electrical and thermal conductivity, but low strength and hardness, and is commonly used in the electrical industry. Brass: Composed of copper and zinc, it has good mechanical and processing properties and is widely used in mechanical manufacturing and architectural decoration. Bronze: composed of copper and tin, with high strength and wear resistance, commonly used in the manufacture of bearings, gears, etc.