Beryllium bronze heat treatment must pay attention to some things

Beryllium bronze is an extremely versatile type of precipitation hardening alloys. After solid solution and aging treatment, the intensity of up to 1250 - 1500MPa( 1250 - 1500 kg) 。 Its features are: heat treatment after solid solution treatment has good plasticity, cold deformation can be performed. But again after aging treatment, has the extremely good elastic limit, also improve hardness and strength. ( 1) Beryllium bronze of the heating temperature of the solid solution treatment generally solid solution treatment - in 780 820 ℃ between, on the elastic component is used as the materials, the 760 - 780 ℃, mainly is to prevent coarse grains impact strength. Solid solution treatment temperature evenness should strictly control the + / - 5 ℃. Holding time can generally be calculated by 1 hour / 25 mm, beryllium bronze in air or oxidizing atmosphere during solid solution heat treatment, surface oxidation film. While strengthening after aging for the mechanical properties of impact is not big, but will affect its cold working die service life. In order to avoid oxidation should be in a vacuum furnace or ammonia decomposition, inert gas, reducing atmosphere ( Such as hydrogen, carbon monoxide, etc. ) In the heating, bright heat treatment effect is achieved. Also, note that try to shorten the transfer time ( The quenching water) , otherwise it will affect mechanical properties after aging. Thin shape materials shall not be more than 3 seconds, the general parts of no more than 5 seconds. Quenching medium water (commonly used No heating requirements) , of course, the parts of complex shape in order to avoid the deformation of oil may be adopted. ( 2) Aging treatment of beryllium bronze beryllium bronze of aging temperature and Be content, including Be less than 2. 1% of the alloy are appropriate for aging treatment. To Be greater than 1. 7% of alloy, the best aging temperature is 300 - 1-330 ℃, holding time 3 hours, According to the parts shape and thickness) 。 Be less than 0. 5% of the high conductivity electrode alloy, because of the higher melting point, the best aging temperature is 450 - 1-480 ℃, holding time 3 hours. In recent years also developed a two stage and multistage limitation, namely first in high temperature short time limitation, and then thermal insulation aging in a low temperature for a long time, the advantage is the performance improvement but reduce the deformation. In order to improve the size precision of the beryllium bronze after aging, can use fixture clamping for aging, sometimes also can use two separate aging treatment. ( 3) To deal with the stress of beryllium bronze beryllium bronze to stress annealing temperature is 150 - 1-200 ℃, holding time 1. 5 hours, can be used to eliminate for metal cutting, straightening processing, cold forming, such as the residual stress, stable parts in use for a long time when the shape and dimension precision.