Thermal treatment method for aluminum alloy cast-spun wheel

Abstract

A thermal treatment method for an A356 aluminum alloy cast-spun wheel is provided. The thermal treatment method is characterized by including the steps of: 1) heating an aluminum alloy wheel cast-spun piece to 540-550° C.; 2) preserving the heat of the aluminum alloy wheel cast-spun piece for 275-285 minutes at the temperature of 540-550° C.; 3) quenching the aluminum alloy wheel cast-spun piece in water of 70-90° C. for 180 seconds; 4) heating the aluminum alloy wheel cast-spun piece to 150-160° C.; 5) preserving the heat of the aluminum alloy wheel cast-spun piece for 175-185 minutes at 150-160° C.; and 6) cooling the aluminum alloy wheel cast-spun piece in air to room temperature.

Claims

1. A thermal treatment method for an aluminum alloy wheel produced by casting and spinning, comprising the steps of: 1) heating the aluminum alloy wheel produced by casting and spinning to 540-550° C.; 2) preserving the heat of the aluminum alloy wheel produced by casting and spinning for 275-285 minutes 540-550° C.; 3) quenching the aluminum alloy wheel produced by casting and spinning in 70-90° C. water for 180 seconds; 4) heating the aluminum alloy wheel produced by casting and spinning to 150-160° C.; 5) preserving the heat of the aluminum alloy wheel produced by casting and spinning for 175-185 minutes at 150-160° C.; and 6) cooling the aluminum alloy wheel produced by casting and spinning in air to room temperature.

2. The thermal treatment method for the aluminum alloy wheel produced by casting and spinning according to claim 1, wherein uniform heating is ensured in step 1).

3. The method according to claim 1, wherein a time for transferring the aluminum alloy wheel produced by casting and spinning from a heat preservation state to a quenching tank in step 3) is within 20 seconds.

4. The thermal treatment method for the aluminum alloy wheel produced by casting and spinning according to claim 1, wherein uniform heating is ensured in step 4).

5. The thermal treatment method for the aluminum alloy wheel produced by casting and spinning according to claim 1, wherein before step 5), the thermal treatment method for the aluminum alloy wheel produced by casting and spinning further comprises a step of performing short-time thermal shock on the aluminum alloy wheel produced by casting and spinning, wherein a time for the short-time thermal shock is 1-3 minutes, and a temperature for the short-time thermal shock is 540-550° C.

6. The thermal treatment method for the aluminum alloy wheel produced by casting and spinning according to claim 1, wherein a quenching medium is agitated in step 3).

Description

DETAILED DESCRIPTION

Embodiment 1

(1) The blank of the hub is produced using a low pressure casting method, the rim and the inner edge are machined by spinning, and then the hub is thermally treated in accordance with the method of this embodiment. The specific method used is as follows: 1) heating an aluminum alloy wheel cast-spun piece to 540-550° C.; 2) preserving the heat of the aluminum alloy wheel cast-spun piece for 280 minutes at the temperature of 540-550° C.; 3) quenching the aluminum alloy wheel cast-spun piece in water of 70-90° C. for 180 seconds; 4) heating the aluminum alloy wheel cast-spun piece to 150-160° C.; 5) preserving the heat of the aluminum alloy wheel cast-spun piece for 180 minutes at 150-160° C.; and 6) cooling the aluminum alloy wheel cast-spun piece in air to room temperature. The quenching medium that is water in step 3) is agitated so that the temperature thereof is as uniform as possible. The temperature range referred in the method of this embodiment means that the temperatures of temperature sensors distributed throughout are within the indicated temperature range. During the setup process, it is not possible to have the same temperature at all locations, but instead have a temperature distribution range.

(2) After thermal treatment, 1000 hubs were produced in test workshops of CITIC Dicastal Co., Ltd. The mechanical properties of the hubs are shown in Table 1.

(3) TABLE-US-00001 TABLE 1 Mechanical properties of hubs in Embodiment 1: Sampling Tensile strength Yield strength Elongation Hardness point Rm (MPa) Rp0.2 (MPa) A5 (%) HBW10/500 Inner ≥260 MPa ≥180 MPa ≥11% ≥80 wheel flange

(4) The produced hubs meet the design requirements of the customer company and have been well received by customers.

Embodiment 2

(5) The blank of the hub is produced using a low pressure casting method, the rim and the inner wheel flange are spun and then the hub is thermally treated in accordance with the method of the present disclosure. The specific method used is as follows: 1) heating an aluminum alloy wheel cast-spun piece to 540-550° C.; 2) preserving the heat of the aluminum alloy wheel cast-spun piece for 280 minutes at the temperature of 540-550° C.; 3) quenching the aluminum alloy wheel cast-spun piece in water of 70-90° C. for 180 seconds; 4) heating the aluminum alloy wheel cast-spun piece to 150-160° C.; 5) preserving the heat of the aluminum alloy wheel cast-spun piece for 180 minutes at 150-160° C.; and 6) cooling the aluminum alloy wheel cast-spun piece in air to room temperature. The quenching medium that is water in step 3) is agitated so that the temperature thereof is as uniform as possible. The temperature range referred in the method of this embodiment means that the temperatures of temperature sensors are within the indicated temperature range. During the setup process of the solid solution furnace, it is not possible to have the same temperature at all locations, but instead have a temperature distribution range.

(6) After thermal treatment, 1000 hubs were produced in test workshops of CITIC Dicastal Co., Ltd. The mechanical properties of the hubs are shown in Table 2.

(7) TABLE-US-00002 TABLE 2 Mechanical properties of hubs in Embodiment 2: Sampling Tensile strength Yield strength Elongation Hardness point Rm (MPa) Rp0.2 (MPa) A5 (%) HBW10/500 Inner ≥260 MPa ≥180 MPa ≥11% ≥80 wheel flange

(8) The produced hubs meet the design requirements of the customer company and have been well received by customers.

Embodiment 3

(9) This embodiment is substantially the same as embodiment 1 in conditions, and the difference is, before step 5), the method further includes a step of performing short-time thermal shock on the aluminum alloy wheel cast-spun piece, in which the time of short-time thermal shock is 3 minutes, and the temperature is 540° C.

(10) After thermal treatment, 1000 hubs were produced in test workshops of CITIC Dicastal Co., Ltd. The mechanical properties of the hubs are shown in Table 3.

(11) TABLE-US-00003 TABLE 3 Mechanical properties of hubs in Embodiment 3: Sampling Tensile strength Yield strength Elongation Hardness Point Rm (MPa) Rp0.2 (MPa) A5 (%) HBW10/500 Inner ≥285 MPa ≥210 MPa ≥10.4% ≥80 wheel flange

Embodiment 4

(12) This embodiment is substantially the same as embodiment 2 in conditions, and the difference is, before step 5), the method further includes a step of performing short-time thermal shock on the aluminum alloy wheel cast-spun piece, in which the time of short-time thermal shock is 1 minute, and the temperature is 550° C.

(13) After thermal treatment, 1000 hubs were produced in test workshops of CITIC Dicastal Co., Ltd. The mechanical properties of the hubs are shown in Table 4.

(14) TABLE-US-00004 TABLE 4 Mechanical properties of hubs in Embodiment 4: Sampling Tensile strength Yield strength Elongation Hardness Point Rm (MPa) Rp0.2 (MPa) A5 (%) HBW10/500 Inner ≥287 MPa ≥212 MPa ≥10.1% ≥80 wheel flange