Testing apparatus for dynamic galvanic corrosion

Abstract

The invention belongs to the technical field of corrosion testes of metal materials, and relates to a testing apparatus for dynamic galvanic corrosion. A rotary electrode sample is embedded in a rotary electrode embedded seat; a non-testing surface of the rotary electrode sample is provided with a threaded hole to realize threaded connection with a rotary shaft; a positive electrode of a galvanic corrosion measurement instrument is connected with the rotary electrode sample through an electric brush; a carborundum grinding column is fixed on two sides of a fixed electrode; a channel is disposed between a fixed electrode embedded seat and a support with adjustable height; the fixed electrode and a cooper conductor are electrically connected through a spring; a negative electrode of the galvanic corrosion measurement instrument is directly connected to the fixed electrode; and the support with adjustable height and the fixed electrode embedded seat are connected by a screw with high dense threads. A testing method comprises three steps of installing the testing apparatus; setting testing conditions and controlling rotating speed; and recording data. The testing apparatus is simple in structure and convenient for operation; the testing method is reliable in principle and strong in practicability; the testing conditions can be realized easily; cost is low; testing efficiency is high; and the testing apparatus is environment-friendly.

Description

Technical field: [0001] The invention belongs to the technical field of metal material corrosion tests, and relates to a new galvanic corrosion test device, in particular to a dynamic galvanic corrosion test device, which realizes the galvanic corrosion test of dissimilar metal materials in a moving state. Background technique: [0002] At present, the corrosion problem is an important factor that affects and restricts the safe use of ships, marine engineering and coastal buildings. Ships, ship-borne equipment, coastal buildings, docks and offshore platforms are in environments with high salinity, high humidity and heavy pollution all year round. , is very prone to corrosion; among many types of corrosion, galvanic corrosion is a relatively common and important type of corrosion. From the design and manufacture of ship-borne equipment, ships and marine engineering equipment, many factors will cause serious damage. Galvanic corrosion; the so-called galvanic corrosion refers t...

AI Technical Summary

Problems solved by technology

In order to prevent local corrosion damage caused by dynamic galvanic corrosion, it is very necessary to study the behavior and law of dynamic galvanic corrosion, and take effective control measures for its corrosion characteristics; most of the galvanic corrosion tests in the existing laboratories are based on National standard GB / T15748-1995 "Galvanic corrosion test method for marine metal materials", in this standard, the corrosion medium is static sea water, the sample area is 1:1 static suspension, the operation method is simple, easy to implement, and the test data is stable , but the disadvantage is that it cannot simulate the flowing seawater environment, nor can it simulate the mutual friction motion of dissimilar metals. In practice, the seawater erosion environment is much more serious than the static seawater corrosion, and the mutual friction between dissimilar metals will also accelerate galvanic corrosion, so The experimental data obtained from static seawater is difficult to truly reflect the true tendency and degree of galvanic corrosion between materials

[0003] Most of the existing technologies are aimed at dynamic friction and wear corrosion and galvanic corrosion respectively. For dynamic friction and wear corrosion, there are generally two test methods: erosion and abrasion. The test methods for simulating seawater erosion include rotary erosion, pipe flow erosion, and jet erosion. etc. For example, the "Pipe-flow Liquid-Solid Two-phase Flow Erosion Corrosion Experimental Device" disclosed in Chinese Invention Patent No. 00253528.9 introduces a pipe-flow type erosion simulation corrosion test device, which provides a method for research or measurement under high flow rate conditions. The influence of the distribution of the local flow velocity and state of the fluid and the movement characteristics of the particles near the pipe wall on the erosion and corrosion of materials; the "jet-type liquid-solid two-phase flow erosion and corrosion experimental device" disclosed in the Chinese Invention Patent No. 200720014413. Real-time measurement of long-term electrochemical parameters under different flow rates, spray angles and medium temperatures; the "multifunctional submerged spray cavitation test device" disclosed in the Chinese invention patent No. 200810249618.6 realizes the simulation of material erosion under different pressure environments Measurement of corrosion performance, such as electrochemical measurement of materials under different cavitation intensities; Chinese invention patent No. 201010603782. The advantages of the erosion corrosion experimental device are that it can simulate the axial erosion corrosion of the inner wall of the pipeline under rotating conditions, and at the same time control the flow rate, medium composition and temperature, as well as real-time electrochemical measurement and weight loss measurement; in practice, for the test method of simulating material wear, At present, there is no recognized evaluation method for the reliability of corrosion and wear test equipment. The existing corrosion and wear test equipment at home and abroad are all designed and manufactured by researchers according to their own research purposes. There is no finalized corrosion and wear testing machine, such as The Chinese invention patent No. 201110207373.2 discloses "a high-temperature and high-pressure in-situ scratch and corrosion wear test device" mainly introduces a high-temperature and high-pressure in-situ scratch corrosion wear test device, which can realize the surface of the sample under high temperature and high pressure. In-situ single scratch and reciprocating corrosion wear research, and can detect the process of sample surface film from destruction to repassivation during the process of scratch or corrosion wear on the surface of the sample

In addition, there are currently many invention patents for galvanic corrosion. For example, a "multi-channel galvanic corrosion experiment data acquisition device" disclosed in the invention patent No. 200420098658.2 introduces a fully automatic multi-channel intelligent acquisition and processing The galvanic corrosion test data acquisition device of the data can measure the galvanic corrosion potential and current of multiple sets of galvanic couples in situ at the same time, the data acquisition is accurate, the efficiency is high, and a lot of manpower and financial resources are saved; the Chinese invention patent No. 200910238567.1 is disclosed "A galvanic corrosion test device" introduces a method for any two different metal materials containing CO 2 / H 2 The galvanic corrosion measurement device in the solution medium of S, which can carry out the galvanic corrosion test device with the same yin and yang area and different area ratio changes, and can also perform high temperature and high pressure galvanic corrosion immersion weight loss tests with different area ratios; the above patents None of the technologies has realized the effective combination of dynamic friction and wear corrosion and galvanic corrosion

In addition, there is a Chinese invention patent No. 201010225412 which discloses "a test method for simulating galvanic corrosion in a seawater scouring environment". This invention combines galvanic corrosion and dynamic friction and wear corrosion, and can realize galvanic corrosion in a simulated seawater scouring environment However, the method introduced in this patent cannot realize the simulation of the working conditions of mutual friction and wear between metals, and in the technical field of galvanic corrosion of metal materials, there is no reference to the friction of dissimilar metal materials under the environmental conditions of flowing seawater (or other corrosive media). There are no identical or similar technical records or literature reports, so it is sought to design a simple, fast and accurate dynamic galvanic corrosion test device for dissimilar metals in flowing seawater or other corrosive medium environments. The galvanic corrosion test in the process of mutual movement or friction has good scientific research significance and practical value

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