On 2018-08-08 14:48:54
On 2018-08-08 14:47:24
On 2018-08-08 11:45:46
What is the heat treatment and quenching process of aluminum alloy?
1. Heat treatment process of aluminum alloy.
The purpose of this process is to make a large number of usable hardening elements, such as copper, magnesium, zinc or multi dissolved solids, become solid melts, which must be kept between 535 ℃ and 550 ℃ for a long enough time of 6-8 hours, so as to obtain a solid solution that is more homogeneous than that of homogeneous.
The solution temperature of aluminum alloy is 530 ° C and 555 ° C. beyond this temperature, aluminum alloy wheels begin to melt into aluminum water.
Key points of aluminum alloy heat treatment process:
A. When heating up, firstly turn on the cooling water of the windmill smoothly, and then turn on the operating temperature setting of the windmill fully. When the combustion condition enters the furnace (the casting is placed with side a facing up, and side a facing down is forbidden (during solution treatment))
B. The solution aging treatment condition is 545 ° c * 8h + 130 ° c * 6h, and the temperature must be stable and uniform, which is determined by the design strength, material, characteristics and test of the wheel rim.
C. The quenching water temperature is 60 ℃ - 80 ℃, and the casting is not easy to deform. The quenching time is calculated from the door to the upper casting full bubble to water, and the time is 16 seconds - 20 seconds to complete the instant quenching.
D. After solution treatment, complete inspection items, deformation inspection, shaping, steel lettering to prevent abnormal quality tracking. After aging, the hardness of each casting on the upper and lower layers of each vehicle is measured, with a value of 65-75hb. It is the same with continuous automatic operation and high-temperature operation. It is required to exit the furnace in advance and then enter the furnace. It is required to enter and exit the furnace regularly according to the time set by the timer.
2. Water quenching delay process of aluminum alloy.
When quenching water, from the solution temperature in the furnace to the time before quenching water, the time of quenching water delay is 15 seconds > 18 seconds. The quenching liquid is usually water, the rest is air or liquid nitrogen, etc., but the stress and distortion caused by quenching shall be considered. Sometimes hot water shall be used to prevent deformation and fracture.
It is analyzed that when the hardenable heat-treated aluminum alloy is quenched to normal temperature, because the solubility of solute is low at low temperature, a saturated and unstable state is produced, so some tissues will precipitate in the base, and the precipitate effect at room temperature is natural aging, and the precipitate at a certain temperature is artificial aging.