Gas adsorption and desorption rate measurement system and measurement method on material surface

Abstract

The invention provides a measuring system for the gas adsorbing rate and the gas desorbing rate on the surface of a material and measuring method. The measuring system comprises a pressure control box, a gas pumping system, a gas-to-be-measured supplying system and a temperature-controllable QCM (Quartz Crystal Microbalance) measuring system, wherein the gas pumping system and the gas-to-be-measured supplying system are respectively communicated with the pressure control box by gas cabin-penetrating flanges; the temperature-controllable QCM supplying system comprises a QCM probe, a QCM signalprocessor and a cooling machine; a metal material to be measured is plated on a surface wafer in the QCM probe; the cooling machine is connected with the QCM probe by a cooling pipeline and is used for controlling the temperature of the surface wafer. By utilization of the measuring system, accurate measurement for gas adsorbing rate and the gas desorbing rate on the surface of the material underlow-temperature and low-pressure conditions can be realized; the measuring method utilizes the measuring system.

Description

technical field [0001] The invention relates to the field of metal material measurement and analysis, in particular to a gas adsorption and desorption rate measurement system and measurement method on a material surface. Background technique [0002] The two-component attitude control engine is the core device of the spacecraft, and the vacuum plume generated during its operation will cause plume pollution to the spacecraft. The inaccurate evaluation of the plume pollution by the spacecraft design department may cause accidents or make the design conservative, which will affect the safety and advancement of the spacecraft. The existing model describing the interaction between plume pollutants and spacecraft materials is the total adsorption model after arrival, which cannot accurately describe the complex mechanism of plume pollution. [0003] Because most of the spacecraft materials are in the recirculation area of ​​the bicomponent engine plume, they have the characterist...

AI Technical Summary

Problems solved by technology

The volumetric method measures the change of pressure in the container or the flow of gas in the relevant pipeline after the material is adsorbed or desorbed. The defect of this method is that the gas not only interacts with the surface of the material to be tested, but also interacts with the wall of the container. Therefore, there is a large error in the measurement results; the mass method measures the mass change of the material to be tested by measuring the mass change after gas adsorption and desorption, and the material to be tested in this method is mostly a specific material that is easy to adsorb gas , as opposed to non-common materials, which are less sensitive to mass changes in the material under rarefied gas conditions

In addition, when the existing technology measures the adsorption and desorption process of the gas and the surface of the material, it is mostly a high-pressure gas. Even when the material desorption process is measured under vacuum, the wall temperature is usually room temperature, which does not meet the requirements of the two-component engine plume. Conditions of action of the flow on the surface of the material

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