CN-121702939-B - Test device and method for material weld joint gassing characteristic analysis under vacuum condition

CN121702939BCN 121702939 BCN121702939 BCN 121702939BCN-121702939-B

Abstract

The invention discloses a test device and a test method for material weld gas release characteristic analysis under a vacuum condition, and relates to the field of material analysis, wherein the device comprises a vacuum pumping system, a measuring system and a standardized sample connected with the measuring system which are mutually communicated; the vacuum air extraction system comprises an air extraction chamber, a vacuum air extraction pump set and a vacuum valve, wherein the air extraction chamber is provided with a first vacuum gauge pipe, and two sides of the air extraction chamber are symmetrically provided with small conductance holes; the measuring system comprises a first testing chamber, a second testing chamber, a third testing chamber, a second vacuum gauge pipe, a third vacuum gauge pipe, a mass spectrometer and a standardized sample, wherein the two testing chambers are respectively provided with the second vacuum gauge pipe, the third vacuum gauge pipe and the mass spectrometer, the standardized sample comprises a welded seam testing piece and a welded seam-free standard piece, the welded seam testing piece and the welded seam-free standard piece are respectively arranged at the openings of the two testing chambers through sealing flanges, the wall thickness and the material are consistent with those of the testing chambers, the effective air release surface area of a base material is equal except a welded seam area, the device is designed with the standardized sample through a symmetrical structure, the equivalent of a testing environment and the comparability of the sample are ensured, the air release characteristic of the welded seam can be accurately quantized, and reliable data support is provided for the optimization of the welding process of a vacuum cavity.

Inventors

YAO ZIYUN
ZHANG YONG
WANG DONG
QIN FEN
XU SHA
ZHANG YUHAN
Deng Qimao
ZHANG XINKAI

Assignees

中国工程物理研究院应用电子学研究所

Dates

Publication Date: 20260508
Application Date: 20260212

Claims (8)

1. The test device for the material weld joint gassing characteristic analysis under the vacuum condition is characterized by comprising a vacuum pumping system, a measuring system and a standardized sample, wherein the vacuum pumping system is communicated with the measuring system, and the standardized sample is connected with the measuring system; The vacuum pumping system comprises a pumping chamber, a vacuum pumping pump set and a vacuum valve, wherein a first vacuum gauge is assembled on the pumping chamber, the pumping chamber is communicated with the vacuum pumping pump set, and flow guide small holes are symmetrically arranged on two sides of the pumping chamber; The measuring system comprises a testing chamber, a second vacuum gauge, a third vacuum gauge and two mass spectrometers, wherein the testing chamber comprises a first testing chamber and a second testing chamber, the second vacuum gauge is assembled in the first testing chamber, the third vacuum gauge is assembled in the second testing chamber, and the two mass spectrometers are respectively assembled in the first testing chamber and the second testing chamber; the standardized test sample comprises a test piece with a weld joint and a standard piece without the weld joint, the test piece with the weld joint and the standard piece without the weld joint are respectively arranged at the openings of the first test chamber and the second test chamber and are connected through a sealing flange, and the effective air release surfaces of the test piece with the weld joint and the standard piece without the weld joint are exposed to the vacuum of the first test chamber and the vacuum of the second test chamber; the wall thickness and the material of the welded test piece and the welded standard piece are consistent with those of the first test chamber and the second test chamber, and the effective air release surface areas of the rest base materials are equal except the welded area of the welded test piece and the welded standard piece; The outer sides of the welded seam test piece and the welded seam-free standard piece are respectively provided with a heating component with the same specification, the heating components are temperature programming desorption components, and the desorption peak temperatures of different gases on the surface of the welded seam can be monitored in real time and the adsorption energy can be calculated; The air extraction chamber, the first test chamber and the second test chamber are all connected with the vacuum air extraction pump set through pipelines, vacuum valves are arranged on the first test chamber and the second test chamber, and the vacuum valves are arranged in pipelines connecting the conductance small holes with the first test chamber and the second test chamber.
2. The test device for analyzing the outgassing characteristics of a welded seam of a material under vacuum conditions according to claim 1, wherein the welded seam of the welded seam test piece is processed on the inner wall or the outer wall of a joint, and the welded seam structure is formed by different welding methods or different joint forms.
3. The test device for material weld outgassing characteristics analysis under vacuum conditions, as set forth in claim 1, wherein the conductance holes are symmetrically arranged along both sides of the pumping chamber and are identical in structure.
4. The test device for analyzing the gas release characteristics of the welding seam of the material under the vacuum condition according to claim 1, wherein the mass resolution of the mass spectrometer can identify trace gas as low as 10 -9 Pa and has a rapid scanning function, and the mass spectrometer can capture the dynamic change process of the gas release of the welding seam.
5. A method for material weld outgassing characteristics analysis under vacuum conditions, characterized in that it is based on the test device according to any of claims 1-4, comprising the following steps: s1, preparing a standard component, namely processing a weld-free standard component by adopting a base material which is the same as a weld to be detected; S2, preparing test pieces, namely processing a series of test pieces with welding seams, wherein the geometric dimensions of the test pieces are consistent with those of the standard pieces in the step S1, and processing the welding seams on the effective deflation surface of each test piece in a different target welding process or joint mode; S3, installing and measuring, namely installing a standard piece without a welding seam in a second test chamber in a sealing way, and installing any test piece with a welding seam in a first test chamber in a sealing way; Starting a vacuum pumping system, opening a vacuum valve, vacuumizing to a preset limit pressure, closing the vacuum valve, setting pretreatment conditions for pretreatment of two samples, after pretreatment is finished, recording pressure values P1, P2 and P3 of a first vacuum gauge, a second vacuum gauge and a third vacuum gauge and detection data of two mass spectrometers at different time intervals when the pressure is stable; S4, calculating the air release rate, namely calculating the total air release rate of the welding seam according to a formula Q=C× (P2-P3), wherein C is a conductance value of a known conductance pore, P2 is the stable pressure of the first test chamber, and P3 is the stable pressure of the second test chamber; normalized area bleed rate is calculated according to the formula q_well=q/a_well, where a_well is the pre-calibrated weld zone measurement surface area.
6. The method for analyzing the deflation characteristics of a material weld under vacuum conditions according to claim 5, wherein in the step S2, the effective deflation surface area, the surface state, the geometric dimension and the wall thickness of all the prepared test pieces except the positions, the forms and the processing technology of the weld areas are different, and the effective deflation surface areas, the surface states, the geometric dimensions and the wall thicknesses of the rest of the base materials are consistent with those of the standard pieces; The prepared test piece is required to detect the air tightness of the welding seam by a helium mass spectrometer leak detector before being installed, so that the quality of the welding seam is ensured to meet the vacuum requirement of a test chamber.
7. The method for analyzing the air release characteristics of the welding seam of the material according to claim 5, wherein the pretreatment conditions in the step S3 comprise a baking temperature and a baking time period, and the heating conditions of the two test chambers are completely consistent in the pretreatment process, so that the air release environment of the background sample and the air release environment of the comparison sample are equivalent.
8. The method for analyzing the gas release characteristics of the material weld under the vacuum condition according to claim 5, wherein in the step S3, the gas release components are analyzed through the mass spectrometer, the desorption peak temperatures of different gases on the surface of the weld are obtained, and a correlation model of adsorption energy and gas release rate is established; if the heating component is a programmed temperature desorption component, synchronously recording desorption peak temperatures of different gases on the surface of the welding seam, and establishing a correlation model of adsorption energy and deflation rate by combining the deflation rate data of the step S4.

Description

Test device and method for material weld joint gassing characteristic analysis under vacuum condition Technical Field The invention relates to the field of material analysis, in particular to a test device and a test method for material weld gas release characteristic analysis under vacuum conditions. Background In the manufacture of ultra-high vacuum equipment (such as particle accelerators, space simulation devices and semiconductor process equipment), large-size vacuum cavities are difficult to integrally process and form, and products are often realized by adopting a component splice welding mode, particularly in the space cavity with a complex structure. The gas release rate and the gas release component of the cavity weld joint area are far higher than those of the base metal due to the high temperature heat cycle and microstructure change, and the gas release rate and the gas release component are one of non-negligible gas sources in a vacuum system. For a large-thickness vacuum chamber, welding seams are usually arranged inside and outside a welding part, and for a plurality of chambers with small size and complex structure, a welding gun cannot enter the chamber, or when strict precision requirements are met on the size of the internal chamber, only the welding can be performed outside. Therefore, when the high vacuum chamber is developed, in the material and process screening stage, the weld joint gassing characteristics of different welding methods (such as argon arc welding, electron beam welding and laser welding) and different joint forms (such as butt joint and angle joint) are accurately evaluated, and the method has great significance in optimizing the vacuum chamber manufacturing process and improving the equipment performance. At present, a vacuum air release rate measuring device based on a small hole conductance method is a general device for measuring the air release rate of a material. However, when applied to weld bleed studies, there are the following significant technical challenges: (1) Sample comparability is poor and conventional methods lack standardized sample designs. If workpieces with different shapes and different welding seam positions are directly taken as samples, the effective air release areas are difficult to uniformly define and calculate, so that the measured air release rate data cannot be compared fairly and accurately, and the advantages and disadvantages of the welding process cannot be truly reflected. (2) The contribution of the welding seam can not be separated, the measured gassing rate is the comprehensive effect of the welding seam and the base metal, the existing method lacks effective technical means, gassing of the welding seam area is separated from the base metal background, and the gassing characteristic of the welding seam is difficult to accurately quantify. (3) The test efficiency is low, no special test sample aiming at weld joint research is needed, the test needs to be specially designed and installed, the process is complex, and high-flux and standardized comparison test of various weld joints can not be realized. Therefore, a test device and a method for analyzing the air release characteristics of a material weld under vacuum condition are now proposed to solve the above problems. Disclosure of Invention The invention overcomes the defects of the prior art and provides a test device and a test method for analyzing the deflation characteristics of a material weld under a vacuum condition. In order to achieve the aim, the technical scheme adopted by the invention is that the test device for analyzing the material weld gas release characteristics under the vacuum condition comprises a vacuum pumping system, a measuring system and a standardized sample, wherein the vacuum pumping system is communicated with the measuring system, and the standardized sample is connected with the measuring system; The vacuum pumping system comprises a pumping chamber, a vacuum pumping pump set and a vacuum valve, wherein a first vacuum gauge is assembled on the pumping chamber, the pumping chamber is communicated with the vacuum pumping pump set, and flow guide small holes are symmetrically arranged on two sides of the pumping chamber; The measuring system comprises a testing chamber, a second vacuum gauge, a third vacuum gauge and two mass spectrometers, wherein the testing chamber comprises a first testing chamber and a second testing chamber, the second vacuum gauge is assembled in the first testing chamber, the third vacuum gauge is assembled in the second testing chamber, and the two mass spectrometers are respectively assembled in the first testing chamber and the second testing chamber; The standardized test sample comprises a test piece with a weld joint and a standard piece without the weld joint, wherein the test piece with the weld joint and the standard piece without the weld joint are respectively arranged at the openings of the first test chamber an