CN102140646A

CN102140646A - Method for improving quality of cleaning aluminum alloy vacuum brazing part

Info

Publication number: CN102140646A
Application number: CN2010106043479A
Authority: CN
Inventors: 涂勇; 张剑波; 姜国建
Original assignee: Guizhou Yonghong Aviation Machinery Co Ltd
Current assignee: Guizhou Yonghong Aviation Machinery Co Ltd
Priority date: 2010-12-24
Filing date: 2010-12-24
Publication date: 2011-08-03

Abstract

The invention discloses a method for improving quality of cleaning an aluminum alloy vacuum brazing part, and belongs to a metal surface cleaning method. The method comprises the following steps of: cleaning and removing oil of the part in aqueous solution of aluminum alloy cleaning agent with the concentration of 2-5 percent and the temperature of 60 DEG C for 240 to 300 seconds; cleaning the cleaned and oil-removed part in water with the temperature of between 55 and 65 DEG C for 30 to 60 seconds; cleaning the part cleaned by hot water in cold water for 30 to 60 seconds; cleaning and polishing the part cleaned by cold water in aluminic acid dehydration solution with the concentration of 1.5-3 percent and the temperature of between 40 and 60 DEG C for 60 to 80 seconds; cleaning the cleaned and polished part in cold water for 30 to 60 seconds again; and cleaning the part cleaned again in water with the temperature of between 70 and 80 DEG C for 20 to 60 seconds again. The method radically overcomes the defects of non-ideal cleaning effect of strong base and strong acid, serious pollution, high danger and the like, and is an ideal method for cleaning aluminum alloy parts.

Description

Improve the method for Aluminum Alloy Vacuum Brazing part cleaning quality

Technical field: the present invention relates to the method on a kind of clean metal surface, relate in particular to a kind of method that the soldering part surface is cleaned of in Aluminum Alloy Vacuum Brazing technology, treating.

Background technology: Aluminum Alloy Vacuum Brazing belongs to solder without soldering acid, it have environmental protection, efficient, weldquality is good, can the welded construction complex product etc. plurality of advantages, obtained widespread use in recent years.Yet the cleaning quality that how to improve Aluminum Alloy Vacuum Brazing piece surface to be welded is the problem that needs to be resolved hurrily always.For a long time, adopt strong acid, strong base solution to clean usually, mainly have following defective:

1) the piece surface corrosion is very inhomogeneous, is difficult to guarantee good joint clearance of brazing;

2) the local cleaning quality of part is difficult to guarantee, thereby usually causes doing over again in a large number;

3) configuration strong acid, highly basic have increased the danger of this work;

4) the easy contaminate environment of the smog that strong acid, highly basic produced;

Owing to there is above-mentioned defective, weld seam exists pore, slag inclusion and defective such as unsaturated, not fine and close easily after the part soldering, therefore is difficult to obtain the weld seam good quality production.

Summary of the invention: at the above-mentioned defective that exists in the prior art, the present invention aims to provide a kind of method that improves Aluminum Alloy Vacuum Brazing part cleaning quality, it can effectively remove the greasy dirt and the oxide film of piece surface, thereby obtain good piece surface state, finally improve the soldered seam quality.

To achieve these goals, the present invention is by the following technical solutions:

1) part is put into to fill mass percent concentration be that 2-5%, temperature are that 60 ℃ the aluminium alloy clean-out system aqueous solution cleans oil removing 240-300 second;

2) will put into 55-65 ℃ hot water through the part that cleans oil removing and clean 30-60 second;

3) will put into cold water through the part that superheated water cleans and clean 30-60 second;

4) will put into that to fill mass percent concentration be that 1.5-3%, temperature are 40-60 ℃ aluminic acid dehydrating solution cleaning polishing 60-80 second through the part that supercooled water cleans;

5) will put into cold water through the part of cleaning polishing and clean 30-60 second once more;

6) will put into 70-80 ℃ hot water through the part that cleans once more cleans 20-60 once more and takes out after second.

The preferred concentration of the aluminium alloy clean-out system aqueous solution is 2%, and the preferred concentration of aluminic acid dehydrating solution is 1.5%.

In technique scheme, described aluminium alloy clean-out system is a kind of neutral cleaners (code name is SR-820CIIT) of being produced by Tianjin Talent Chemical Co., Ltd, and it is that the additive of benzotriazole, 3-5% of 10-15% fatty alcohol-polyoxyethylene ether, 10-15% aliphatic amide, 3-5 is formulated by mass percent; The pH value of its stoste is 6-7.5, and is soluble in water, is mainly used in the cleaning before chemical membranes such as various aluminium oxidations, phosphatization are handled.It is a kind of acid stripper of being produced by Tianjin Talent Chemical Co., Ltd (code name is MS-86) that described aluminic acid takes off, and it is that the inhibiter of mineral acid, 5-15% alkylphenol polyoxyethylene, 1-5% of 30-60% is formulated by mass percent; Soluble in water, boiling point more than or equal to 100 ℃, the pH value of its stoste less than 1; Be mainly used in the cleaning of peeling off of aluminium and sclerosis aluminium.

Compared with the prior art, therefore the present invention can remove the greasy dirt and the oxide film of piece surface effectively owing to adopted technique scheme, when vacuum brazing, help solder wetting, flow and sprawl, finally improve the product quality of vacuum brazing.The present invention has deficient, the advantages such as the cycle is short, cost is low, environmental protection of cleaning process; Thoroughly overcome strong acid, the highly basic cleaning performance is undesirable, seriously polluted, dangerous defective such as big.

According to the actual fact, adopt the inventive method cleaning aluminum alloy vacuum brazing part, the weldquality qualification rate after the vacuum brazing rises to 90% by original less than 50%, has obtained good effect.Below be three groups of test datas that the aluminium alloy plate fin radiator (totally 2000 covers) that adopts the inventive method to produce is carried out.

Table 1: product leakage test

Batch	The product tricks	Leak number	Passing number	Qualification rate %
					1	100	3	97	97
2	240	0	240	100
					3	720	50	670	93
4	540	40	500	92.5
					5	400	39	361	90.2

Table 2: product bursting strength sampling test

Table 3: product fatigue strength sampling test (frequency: 2Hz, circulating pressure: 1.6MPa)

Batch	The sampling tricks	Bursting strength (Mpa)	Qualification rate %
				1	2	1600000、165000	100
2	2	2000000、20050000	100
				3	3	1750000、1806000、1700000	100
4	1	1500000、1600000	100
				5	2	1850000、1900000	100

From above-mentioned test-results as can be known, technology of the present invention is (bursting strength 9Mpa, fatigue strength 1000000 times) under the prerequisite that satisfies the every performance index of product fully, the qualification rate of product can be brought up to more than 90%.

Embodiment: the invention will be further described below in conjunction with specific embodiment:

Embodiment 1

1) part is put into fill that mass percent concentration is 2%, temperature is that 60 ℃ the aluminium alloy clean-out system aqueous solution cleans oil removing 240 seconds;

2) will put into 55 ℃ hot water through the part that cleans oil removing cleaned 30 seconds;

3) will put into cold water through the part that superheated water cleans cleaned 30 seconds;

4) will put into through the part that supercooled water cleans fill that mass percent concentration is 1.5%, temperature is 40 ℃ aluminic acid dehydrating solution cleaning polishing 60 seconds;

5) will put into cold water through the part of cleaning polishing cleaned 30 seconds once more;

6) will put into 70 ℃ hot water through the part that cleans once more cleans once more and takes out after 20 seconds.

Embodiment 2

1) part is put into fill that mass percent concentration is 5%, temperature is that 60 ℃ the aluminium alloy clean-out system aqueous solution cleans oil removing 300 seconds;

2) will put into 65 ℃ hot water through the part that cleans oil removing cleaned 60 seconds;

3) will put into cold water through the part that superheated water cleans cleaned 60 seconds;

4) will put into through the part that supercooled water cleans fill that mass percent concentration is 3%, temperature is 60 ℃ aluminic acid dehydrating solution cleaning polishing 80 seconds;

5) will put into cold water through the part of cleaning polishing cleaned 60 seconds once more;

6) will put into 80 ℃ hot water through the part that cleans once more cleans once more and takes out after 60 seconds.

Claims

1. method that improves Aluminum Alloy Vacuum Brazing part cleaning quality is characterized in that concrete steps are as follows:

2) will put in 55-65 ℃ the hot water through the part that cleans oil removing and clean 30-60 second;

6) will put through the part that cleans once more and clean 20-60 once more in 70-80 ℃ the hot water and take out after second.

2. the method for raising Aluminum Alloy Vacuum Brazing part cleaning quality according to claim 1 is characterized in that: the concentration of the aluminium alloy clean-out system aqueous solution is 2%, and the concentration of aluminic acid dehydrating solution is 1.5%.