CN1710114A - A post-processing method for steel-backed aluminum-based solid-liquid phase composite plate - Google Patents

Abstract

The invention discloses an after treatment of aluminum based steel-back solid-liquid phase complex board. Roll the complex board on the precise rolling mill at a draft of 1.5 to 3.5 percents. The contraction difference between the aluminum cover and the steel back in complex cooling and coagulating period, is compensated with the deformation difference between the aluminum covering layer and the steel back, further reducing the boundary extra stress so to improve the boundary shearing strength of the complex board in a simple and convenience way, resolving the problem that original after treatment of the aluminum based iron back solid-liquid phase complex board is of excessive power consumption and low boundary shearing strength enhancement.

Description

A post-processing method for steel-backed aluminum-based solid-liquid phase composite plate

technical field

The invention relates to a method for post-processing the interface shear strength of a steel-backed aluminum-based solid-liquid phase composite plate.

Background technique

The steel-backed aluminum-based solid-liquid phase composite plate is a composite plate composed of a solid steel plate and an aluminum-based alloy liquid, and is composed of a steel back and an aluminum-based cladding. Since the expansion coefficient of the aluminum-based cladding is significantly greater than that of the steel back, the shrinkage of the aluminum-based cladding is much greater than that of the steel back during the solidification and cooling process after the steel-backed aluminum-based solid-liquid phase recombination, but Since the strength of the aluminum-based cladding is much smaller than that of the steel back, the steel back strongly hinders the normal shrinkage of the aluminum-based cladding at the composite interface, thus generating considerable additional stress at the composite interface. After compound forming, the stress remains on the interface of the composite plate, and is superimposed on the stress generated by the subsequent process, which intensifies the damage to the composite interface. Therefore, after compound forming, the composite plate needs to be post-processed to fully reduce the additional stress on the interface. , so that the composite plate interface shear strength can be improved.

At present, the diffusion annealing method is mainly used to post-treat the composite plate. The treatment time is usually more than 10 hours, and the annealing temperature is as high as 300°C. During the long-term high-temperature annealing process, the atoms in the additional stress region can obtain enough energy to migrate from the high-energy equilibrium position to the low-energy equilibrium position, thereby reducing the additional stress on the interface and improving the interface shear strength. However, for steel-backed aluminum-based solid-liquid phase composite panels, long-term high-temperature diffusion annealing not only consumes a lot of energy and increases costs, but also forms a thick layer of brittle hard iron-aluminum compound over 80 μm at the composite interface, resulting in embrittlement of the composite interface. In this way, while reducing the additional stress on the interface, the interface embrittlement will also limit the improvement of the shear strength of the composite interface, and the shear strength of the composite interface is only increased from 70MPa to 71MPa.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the post-treatment method of steel-backed aluminum-based solid-liquid phase composite plate diffusion annealing "large energy consumption and small increase in interfacial shear strength", and provide a method that can compensate for the aluminum-based cladding The difference in shrinkage produced during solidification and cooling with the steel back after solid-liquid phase recombination reduces the additional stress on the composite interface and further improves the interfacial shear strength of the steel-backed aluminum-based solid-liquid phase composite plate.

The technical solution adopted by the present invention to solve the technical problem is: rolling the steel-backed aluminum-based solid-liquid phase composite plate at a reduction rate of 1.5-3.5% on a precision rolling mill at room temperature.

The reduction rate is the difference between the thickness of the composite plate before rolling and the thickness after rolling and then divided by the thickness before rolling.

Since the strength of the aluminum-based cladding is much smaller than that of the steel back, the deformation of the aluminum-based cladding is much greater than that of the steel back during the rolling process. The difference in back deformation is used to make up for the difference in shrinkage between the aluminum-based cladding and the steel back during the composite solidification and cooling process, thereby reducing the additional stress at the interface of the composite panel, thereby further improving the shear strength of the interface of the composite panel.

The reduction rate of the post-rolling treatment is very important. If the reduction rate is less than 1.5%, the difference in deformation between the aluminum-based cladding and the steel back produced by the rolling treatment cannot fully compensate for the difference between the aluminum-based cladding and the steel back during the composite solidification and cooling process. The difference in the shrinkage of the steel back cannot achieve the purpose of fully reducing the additional stress at the interface of the composite plate; if the reduction rate is greater than 3.5%, the difference in the deformation of the aluminum-based cladding and the steel back produced by the rolling process can make up for it. The difference in shrinkage between the aluminum-based cladding and the steel back during the composite solidification and cooling process results in a difference in the deformation of the new aluminum-based cladding and the steel back, and a new additional stress is formed at the composite interface, resulting in shearing of the composite interface. decrease in shear strength. Therefore, the post-rolling reduction rate range of 1.5-3.5% can make up for the shrinkage difference between the aluminum-based coating and the steel back during the composite solidification and cooling process, and effectively improve the interfacial shear strength.

Compared with the prior art, the present invention has the beneficial effects that: using the present invention, the steel-backed aluminum-based solid-liquid phase composite plate is subjected to post-rolling treatment, and the shear strength of the composite interface is increased from 70MPa to 75-82MPa, saving energy and The effect of increasing the interfacial shear strength is very good. The method of the invention is simple and convenient.

Detailed ways

At room temperature, on a precision rolling mill, rolling is carried out at a reduction rate of 1.5-3.5% for the steel-backed aluminum-based solid-liquid phase composite plate. The difference in the deformation of the aluminum-based cladding and the steel back produced by the rolling process is used to compensate for the difference in the shrinkage of the aluminum-based cladding and the steel back during the composite solidification and cooling process, thereby reducing the additional stress at the interface of the clad plate and improving the interface shear of the clad plate. cutting strength.

Specific application one

For the solid-liquid phase composite plate composed of 1.2mm thick 08Al steel plate and 1.0mm thick industrial pure aluminum cladding, at room temperature, on a precision rolling mill, carry out post-rolling treatment with a reduction rate of 3.5%, and the clad plate composite interface The shear strength increased from 70MPa before rolling to 82MPa after rolling.

Specific application two

For the solid-liquid phase composite plate composed of 1.2mm thick 08Al steel plate and 2.0mm thick Al-28Pb coating, at room temperature, on a precision rolling mill, carry out post-rolling treatment with a reduction rate of 3%, and the composite interface of the clad plate The shear strength increased from 70MPa before rolling to 76MPa after rolling.

Specific application three

For the solid-liquid phase composite plate composed of 1.2mm thick 08Al steel plate and 2.0mm thick Al-20Sn cladding, at room temperature, on a precision rolling mill, carry out post-rolling treatment with a reduction rate of 2%, and the composite interface of the clad plate The shear strength increased from 70MPa before rolling to 76MPa after rolling.

Specific application four

For the solid-liquid phase composite plate composed of 1.2mm thick 08Al steel plate and 2.0mm thick Al-7Gr coating, at room temperature, on a precision rolling mill, carry out post-rolling treatment with a reduction rate of 1.5%, and the clad plate composite interface The shear strength increased from 70MPa before rolling to 75MPa after rolling.

Claims (1)

1. A post-processing method for a steel-backed aluminum-based solid-liquid phase composite plate, characterized in that, at room temperature, on a precision rolling mill, the steel-backed aluminum-based solid-liquid phase composite plate is subjected to a reduction rate of 1.5-3.5 % rolling, using the difference in the deformation of the aluminum-based cladding and the steel back produced by the rolling process to compensate for the difference in shrinkage between the aluminum-based cladding and the steel back during the composite solidification cooling process, thereby reducing the additional stress on the composite plate interface, Improve the shear strength of the composite plate interface.