What is beryllium copper? What is the heat treatment temperature and hardness of beryllium copper
What is beryllium copper? What is the heat treatment temperature and hardness of beryllium copper
What is beryllium copper? Beryllium copper is an extremely versatile precipitation hardening alloy. After solution and aging treatment, the strength can reach 1250-1500MPa. Its heat treatment features are: after solution treatment, it has good plasticity and can be deformed by cold working. However, after the aging treatment, it has an excellent elastic limit, and the hardness and strength are also improved. The heat treatment of beryllium copper can be divided into annealing treatment, solution treatment and aging treatment after solution treatment. To what degree is beryllium copper heat treated? What is the hardness of beryllium copper? This article will introduce the heat treatment temperature and hardness of beryllium copper in detail.
What is beryllium copper?
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 electrical 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 of 930℃ After softening, hardness 135±35HV
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. 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.
Material grades Intermediate soft annealing Stabilized tempering Stress relief tempering
Temperature time (h) Temperature time (h) Temperature time (h)
QBe1.7 540~560 2~4 110~130 4~6 200~250 1~2
QBe1.9 540~560 2~4 110~130 4~6 200~250 1~2
The production steps of beryllium copper alloy plates, strips and strips in the production process of beryllium copper alloy are ingot casting - surface milling - heating (800 degrees Celsius - 900 degrees Celsius) - hot rolling - water quenching - milling surface ---Cold rolling---Degreasing---Solid solution heat treatment---Pickling---Passivation.
How many degrees and hardness of beryllium copper heat treatment
Beryllium copper, also known as beryllium bronze, is the "king of elasticity" in copper alloys. After solution aging heat treatment, products with high strength and high electrical conductivity can be obtained. High-strength cast beryllium bronze alloy, after heat treatment, not only has high strength, high hardness, but also has the advantages of wear resistance and corrosion resistance, excellent casting performance, beryllium bronze alloy is suitable for manufacturing various molds, wear-resistant parts such as cams, Gears, worm gears, bearings, etc. High conductivity cast beryllium copper alloy, which has high electrical conductivity and thermal conductivity after heat treatment, beryllium copper alloy is suitable for making switch parts, strong contacts and similar current-carrying components, making clamps, electrode materials and plastic molds for resistance welding , Hydroelectric continuous casting machine mold inner sleeve, etc. High beryllium copper has the characteristics of high strength, high hardness, high conductivity, high elasticity, wear resistance, fatigue resistance, corrosion resistance and small elastic hysteresis. It is mainly used in temperature controllers, mobile phone batteries, computers, auto parts, micro Motors, brush needles, advanced bearings, glasses, contacts, gears, punches, various types of non-sparking switches, various types of welding electrodes and precision casting molds, etc.
Beryllium bronze is a typical aging precipitation strengthened alloy. The typical heat treatment process of high-strength beryllium bronze is to keep the temperature at 760 ~ 830 ℃ for an appropriate time (at least 60 minutes per 25mm thick plate), so that the solute atomic beryllium is fully dissolved in the copper matrix to form the α phase of the face-centered cubic lattice. Supersaturated solid solution. Subsequently, the temperature was kept at 320-340 °C for 2-3 h to complete the process of desolubilization and precipitation to form a γ' phase (CuBe2 metastable phase). The coherence of this phase with the matrix creates a stress field that strengthens the matrix. The typical heat treatment process of high-conductivity beryllium bronze is to keep for a period of time at a high temperature of 900-950 °C to complete the solid solution process, and then keep it at 450-480 °C for 2-4 hours to achieve the desolubilization and precipitation process. Since more cobalt or nickel is added to the alloy, its dispersion strengthening particles are mostly intermetallic compounds formed by cobalt or nickel and beryllium. In order to further improve the strength of the alloy, a certain degree of cold working is often performed on the alloy after the solution heat treatment and before the aging heat treatment, in order to achieve the comprehensive strengthening effect of cold work hardening and age hardening. Its cold working degree generally does not exceed 37%. Solution heat treatment should generally be carried out by the alloy manufacturer. After the user punches the solution heat-treated and cold-rolled strips into parts, they then self-aging heat treatment to obtain high-strength spring elements.
High-performance beryllium bronze mold material hardness is between (HRC) 38-43, density is 8.3g/cm3, the main addition element is beryllium, containing beryllium 1.9%-2.15%, it is widely used in plastic injection molding. Die cores, die casting punches, hot runner cooling systems, thermal nozzles, integral cavities of blow molds, automotive molds, wear plates, etc.
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Beryllium copper calculation formula:
The formula for calculating the weight of beryllium copper rod: radius x radius x 3.14 x length x density (8.9)/1000000
The formula for calculating the weight of beryllium copper plate: length x width x thickness x density (8.9)/1000000
The formula for calculating the weight of beryllium copper tape: length x width x thickness x density (8.9)/1000000
The formula for calculating the weight of beryllium copper wire: radius x radius x 3.14 x length x density (8.9)/1000000
Calculation formula for the weight of beryllium copper flat bar: length x width x thickness x density (8.9) /
The above is an introduction to the relevant knowledge about beryllium copper. The beryllium copper strip is used in micro-motor brushes, mobile phones, batteries, and products, and is an indispensable and important industrial material for national economic construction. When the strength of the material is expressed by the hardness test value, it cannot replace the tensile strength, and when both the tensile strength and the hardness value are given, the tensile value is given priority. The hardness value is for reference only.