A low-temperature alloy co-infiltration metal anticorrosion process

Abstract

The invention belongs to the technical field of metal heat treatment and metallurgy combination, further belongs to the technical field of metal surface corrosion prevention, and particularly relates to a low-temperature alloy co-penetration metal corrosion prevention technology. The technology includes the steps of workpiece pretreatment, furnace charging, heating, electrolytic polishing, passivating treatment and the like, wherein heating is carried out at 200-380 DEG C, and heat preservation is carried out for 1-1.5 h. Compared with other existing high-temperature galvanization corrosion prevention technologies, the technology has the advantages that the thickness uniformity of a coating is good, the bonding strength of an alloy co-penetration corrosion prevention layer and a metal matrix is high, hardness is high, abrasion resistance and scratch resistance are high, influences on the mechanical performance of components are small, hydrogen embrittlement is avoided, the treatment technology is free of pollution, and corrosion resistance and oxidation resistance are good, and therefore the technology has high application and popularization value.

Description

technical field [0001] The invention belongs to the technical field of combining metal heat treatment and metallurgy, and furthermore, belongs to the technical field of metal surface anticorrosion. More specifically, the invention relates to a low-temperature alloy co-infiltration metal anticorrosion process. Background technique [0002] In the prior art, the products treated with alloy co-infiltration anticorrosion technology are mainly steel products, which involve necessary accessories in many industries such as electric power, railways, highways, automobiles and military equipment, such as commonly used outdoor standard parts, screws, etc. , Nuts, railway rail buckle accessories, signal equipment, power excavation pipes, cable brackets, etc. For these accessories, not only the inherent performance of the workpiece is required to be high, but also the workpiece must not rust for 25 years, and there is also a high requirement for the tensile load between threads. [0003...

AI Technical Summary

Problems solved by technology

[0004] The technical defects of the existing powder hot-dip zinc mainly include: 1. After heating the zinc, in the processes such as nitric acid light emission and chromic acid passivation, chemical raw materials such as nitric acid are used, which is prone to serious heavy metal chromium pollution, not only pollution The environment will also damage the physical and mental health of production personnel, and hydrogen embrittlement will also occur for high-strength bolts and spring workpieces; 2. In order to ensure a certain anti-corrosion performance, a thicker zinc sherardizing layer is required, generally not less than 40μm, It affects the tolerance size between the threads, so that the nuts cannot be screwed on during construction, and the nuts must be enlarged. However, after the nuts are enlarged, it may cause looseness between the threads and insufficient pulling force, which poses a great hidden danger in safety; 3. Powder penetration Zinc heating process, the heating temperature is 400 ℃ ~ 480 ℃, the temperature is high, resulting in secondary tempering of high-strength bolts and spring workpieces, reducing their mechanical properties and fatigue life