Beryllium copper as a castable wrought alloy beryllium copper alloy, also known as beryllium bronze, beryllium copper alloy. It is an alloy with good mechanical, physical and chemical comprehensive properties. After quenching and tempering, it has high strength, elasticity, wear resistance, fatigue resistance and heat resistance. At the same time, beryllium copper also has high electrical conductivity. , thermal conductivity, cold resistance and non-magnetic, no sparks when impacted, easy to weld and braze, excellent corrosion resistance in atmosphere, fresh water and sea water.
It is a high-grade elastic material with the best performance among copper alloys. It has high strength, elasticity, hardness, fatigue strength, small elastic lag, corrosion resistance, wear resistance, cold resistance, high conductivity, non-magnetic, and no sparks when impacted. A series of excellent physical, chemical and mechanical properties. The color of beryllium copper generally shows two colors of red or yellow. It is normal for the color of beryllium copper to appear yellow and red, because the chemical reaction of oxidation occurs during the production and storage process, and the color changes.
Parameters: Density 8.3g/cm3 Hardness before quenching 200-250HV Hardness after quenching ≥36-42HRC Quenching temperature 315℃≈600℉ Quenching time 2 hours
Softening temperature 930℃ After softening, hardness 135±35HV, tensile strength ≥1000mPa
Beryllium copper is divided into high beryllium copper and low beryllium copper. High beryllium copper refers to beryllium copper with a beryllium content greater than 2.0. Beryllium copper is a resistance welding electrode material for welding, with good electrical and thermal conductivity and high hardness. When welding, the electrode wear is less, the speed is fast, and the cost is low.
Beryllium Copper Production Process
The production process of beryllium copper is divided into four steps: the production of beryllium-copper master alloy by carbothermal reduction method, the smelting of beryllium copper alloy, the ingot of copper alloy and the production of beryllium copper alloy plate, strip and strip.
The production of beryllium-copper master alloys by carbothermal reduction refers to the direct reduction of beryllium in beryllium oxide with carbon in molten copper, followed by alloying in copper. The production of beryllium-copper master alloy by carbothermic reduction in industry is carried out in an electric arc furnace. The electric arc furnace is placed in a sealed container. The operator wears a gas mask. % of carbon powder is mixed in a ball mill and ground, and then a layer of copper, a layer of beryllium oxide and carbon powder mixture are loaded into the electric arc furnace in batches, energized and melted. When cooled to 950 degrees Celsius – 1000 degrees Celsius, the alloy name beryllium carbide, carbon, and residual powder float, slag, and then cast into 2.25 kg or 5 kg ingots at 950 degrees Celsius.
The charge used in smelting beryllium copper alloy includes new metal, scrap, secondary remelting charge and master alloy.
Beryllium generally uses beryllium-copper master alloy (containing beryllium 4%); nickel sometimes uses new metal, that is, electrolytic nickel, but it is better to use nickel-copper master alloy (containing 20% ​​nickel); cobalt uses cobalt-copper master alloy ( Cobalt 5.5%), and some directly use pure cobalt; titanium is added by titanium-copper master alloy (containing 15% titanium, and some also contain 27.4% titanium), and some directly add sponge titanium; magnesium is magnesium- Copper master alloy (containing 35.7% magnesium) was added.
Chips (milling chips, cutting chips, etc.) and small corner scraps generated during processing are generally cast into ingots after secondary remelting as the smelting charge; in addition to the regenerated remelting material, when batching It is also common to add some casting waste and machining waste directly to the furnace.
The ingot of beryllium copper alloy is divided into non-vacuum ingot and vacuum ingot. The non-vacuum ingot casting methods currently used in the practice of beryllium copper alloy production include inclined iron mold ingot casting, flowless ingot casting, semi-continuous ingot casting and continuous ingot casting. The first two methods are only used in factories with smaller production scales.
Experts said that in order to obtain beryllium-copper alloy ingots with low gas content, small segregation, less inclusions, and uniform and dense crystal structure, the best way is to vacuum ingots after vacuum smelting. Vacuum ingot casting has a significant effect on ensuring the content of easily oxidizable elements such as beryllium and titanium. When necessary, inert gas can be introduced to protect the ingot casting process.
Definition of beryllium copper heat treatment: heat treatment of beryllium bronze The heat treatment of beryllium bronze can be divided into annealing treatment, solution treatment and aging treatment after solution treatment.
The beryllium copper retreat (return) treatment is divided into: (1) Intermediate softening annealing, which can be used for the softening process in the middle of processing. (2) Stabilized tempering is used to eliminate the machining stress generated during precision springs and calibration, and stabilize the external dimensions. (3) Stress relief tempering is used to eliminate the machining stress generated during machining and calibration.