The heat treatment process of Cu-Be alloy is mainly heat treatment tempering quenching and age hardening. Unlike other copper alloys whose strength is obtained only by cold drawing, wrought beryllium is obtained by cold drawing and thermal aging hardening to 1250 to 1500 MPa. Age hardening is generally referred to as a precipitation hardening or heat treatment process. The ability of beryllium copper alloy to accept this type of heat treatment process is better than other alloys in terms of forming and mechanical equipment performance. For example, complex shapes can be achieved at the maximum strength and strength levels of all other copper-based alloys, that is, under cold rolling and subsequent aging of the raw material.

The whole process of age hardening of high-strength copper beryllium alloy C17200 is described in detail below, as well as the special heat treatment process of forging and forging alloys, the strongly recommended electric furnace for heat treatment, surface air oxidation and basic heat treatment tempering and quenching methods.

In the whole process of aging hardening, external economical beryllium-rich particles will be generated in the metal material cultivation substrate, which is a reflection of diffusion control, and its strength will change with aging time and temperature. The highly recommended International Standard Time and Temperature allows parts to reach their maximum strength within two to three hours without compromising strength through prolonged exposure to temperature. For example, the C17200 alloy response graph on the figure shows how ultra-low temperature, standard temperature and high aging temperature compromise the alloy’s peak properties and the time it takes to achieve peak strength.

It can be seen from the figure that at the ultra-low temperature of 550°F (290°C), the strength of C17200 increases slowly, and does not reach the highest value until about 30 hours later. At a standard temperature of 600°F (315°C) for 3 hours, the intensity transition of C17200 is not large. At 700°F (370°C), the intensity peaks within thirty minutes and decreases substantially immediately. To put it simply, as the aging temperature increases, the time required to achieve the highest strength and the maximum strength that can be used will decrease.

C17200 copper beryllium can be embrittled with different strengths. The embrittlement peak refers to the embrittlement that achieves greater strength. Alloys that are not aged to maximum strength are unaged, and alloys that exceed their maximum strength are overaged. Insufficient embrittlement of beryllium improves ductility, uniform elongation and fatigue strength, while too much embrittlement improves electrical conductivity, heat transfer and gauge reliability. Beryllium Beryllium does not catalyze at room temperature even if stored for long periods of time.

The tolerance for age hardening time lies in temperature control and final property specification. In order to better achieve the best application period at standard temperature, the melting furnace time is generally controlled within ±30 minutes. However, for high temperature embrittlement, a more precise clock frequency is necessary to prevent averaging. For example, be sure to control the embrittlement time of C17200 at 700°F (370°C) to within ±3 minutes to maintain optimum performance. Similarly, because the response curve of embrittlement is greatly improved in the original link, the independent variables of the whole process must also be strictly controlled for insufficient embrittlement. During the specified age hardening cycle time, heating and cooling rates are not critical. However, to ensure that the part is not prone to gradual embrittlement until the temperature is reached, a thermal resistor can be placed to determine when the desired temperature is achieved.

Age hardening machinery and equipment

Circulating system gas furnace. The circulating system gas furnace is temperature controlled at ±15°F (±10°C). It is proposed to carry out a standard age hardening solution for copper beryllium parts. This furnace is designed to accommodate both high-volume and low-volume parts and is ideal for testing stamping die parts on brittle media. However, because of its purely thermal quality, it is important to prevent insufficient embrittlement or too short embrittlement cycle times for quality parts.

Chain type embrittlement furnace. Strand aging furnaces with a defensive atmosphere as a heating substance are suitable for the production and processing of many beryllium copper coils generally in a long furnace, so that the raw material can be expanded or coiled. This allows better control of time and temperature, prevents partial symmetry, and allows for special periods of insufficient or high temperature/short aging and selective hardening.

Salt bath. It is also proposed to use a salt bath for age-hardening treatment of beryllium copper alloys. Salt baths can provide rapid and uniform heating and are recommended for use in all temperature hardening areas, especially in the case of high temperature embrittlement in the short term.

Annealing furnace. Vacuum pump embrittlement of copper beryllium parts can be done successfully, but be careful. Because the heating of the annealing furnace is only by means of a radiation source, it is difficult to uniformly heat the heavily loaded parts. The parts that load the outside are more immediately radiated than the internal parts, so the temperature field after the heat treatment process will change the performance. In order to better ensure uniform heating, the load should be limited, and the parts must be protected from the heating solenoid. The annealing furnace can also be used to backfill with rare gases such as argon or N2. Likewise, unless the furnace is equipped with a circulating system cooling fan, be sure to maintain the parts.