Method of heat treatment of castings from magnesium alloys

 

(57) Abstract:

The invention relates to a method of heat treatment of products made of magnesium alloys, in particular, to a heat treatment arms sporting bows. The method involves heating to the hardening temperature and the cooling air flow from the end sections of the arms to the Central with the initial flow temperature 16-30°C and an air flow of 150-300 m3/min .

The invention relates to the production of castings from magnesium alloys, in particular to the manufacture of arms sporting bows.

There is a method of heat treatment of castings of magnesium alloys, which consists in heating the billets to the hardening temperature and cooling them in air flow.

However, it is not possible to produce differential cooling of different parts of the blanks, and it is less intense cooling her face areas. This reduces the operational properties of blanks intended for the manufacture of arms sports bows, as it does not ensure the required plasticity of the Central part of the handle and at the same time the required rigidity of its end sections.

The aim of the invention is elecrtonic parts.

According to the proposed method the workpiece for sports bow magnesium alloy is heated to the hardening temperature and is cooled by an air stream with an initial temperature 16-30aboutC and an air flow of 150-300 m3/min, while the flow of air passing from the end to the middle part of the workpiece is gradually heated, which leads to more intensive mechanical cooling zones and less intense - the middle part, thereby providing a different strength of the Central and peripheral zones of the billet arm.

The temperature range 16-30aboutWith determined experimentally by studies which found that at temperatures below 16aboutWith the efficient differential cooling and practically blank has a homogeneous structure and properties throughout the volume. At temperatures above 30aboutWith require higher air flow, which leads to increased energy consumption, and create poor working conditions for staff. The interval of flow of the cooling medium (air) 150-300 m3rpm is selected from the conditions for optimal energy cost and obtain the desired distribution of the strength characteristics of the zones serotonin and Central zones of the workpiece and thereby deteriorate the performance of the arm. The increase in consumption above 300 m3rpm is impractical for economic reasons (increase of energy consumption and the working fluid), and also deterioration of working conditions of staff.

P R I m m e R. Billet magnesium alloy ML-10 was subjected to heating to 53010aboutWith and spent cooling air flow with an initial temperature 16-30aboutAnd air flow 150-300 m3/min. While cooling led from the end sections of the arms to the Central, so that the temperature gradually increased, making the mechanical parts were cooled more intensively than the middle part. It was established experimentally that when using the proposed technical solutions in the transition from the end sections of the arm to the middle part there is a change in the velocity of propagation of acoustic waves in average by 5%, which improves the damping properties of the arm and thereby improve its performance properties.

METHOD of HEAT TREATMENT of CASTINGS FROM MAGNESIUM ALLOYS, mainly handles sports bows, including heating to the hardening temperature and the cooling air flow, characterized in that, to improve ekspluatatsionnyi air flow out from the end sections of the arms to the Central with the initial temperature of the stream 16 30oC and an air flow of 150 - 300 m3/min.

 

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