JPS61286061A - Jig member for soldering - Google Patents

Abstract

PURPOSE:To improve the life of a jig member for soldering and to obtain stably a joint part having high accuracy by adjusting the part to contact with molten solder to specific surface roughness and coating a stainless steel or the like to be used as a base metal with a material which is hardly wettable with solder. CONSTITUTION:A film is not particularly limited if the material thereof has the non-wettability with solder, such as the oxide, nitride, carbide or carbonitride of Ti, Zr, Al, Si, B, among which TiN is more preferable. The material for the base metal is selected from any of a sintaless steel, heat resisting steel or ferrous heat resisting alloy. The surface film is formed to <=10mu on the base metal and the surface roughness of the part to contact with the solder is adjusted to <=3mu, by which the local sticking of the solder is prevented. The good film is obtd. if said film is formed by ion plating, sputtering or vacuum deposition. The life of the member is thus improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a soldering jig member,
For example, the present invention relates to a member such as a support rod for an object to be soldered used in an automatic soldering device, which is required to have the property that solder does not adhere even when it comes into contact with molten solder.

[Conventional technology]

Conventionally, a single piece of tungsten has been used as a support rod that comes into direct contact with molten solder, as disclosed in JP-A-58-81561.

[Problem that the invention seeks to solve]

Conventional support rods for soldering are made of tungsten, which is very expensive and has poor workability, making it difficult to process with high precision. As a result, solder, which should not originally adhere to the tungsten support rod, adheres locally starting from defects such as processing scratches, resulting in a significant decrease in the number of repeated uses (life) of the support rod, or to the soldering object. There were problems such as poor quality.

[Means for solving problems]

In the present invention, at least the portion that contacts the melting solder has a surface roughness of 3μ or less, and is made of Ti and Zr.

A1. SL, B oxide, nitride, carbide, carbonitride,
Covered with a substance that is difficult to wet with solder made of one or more of borides, Mo, W, or their alloys, and the base material is made of stainless steel, heat-resistant steel, or iron-based super heat-resistant alloy. By using the soldering jig member, the above-mentioned problems are solved. Furthermore, it is preferable that the coating with a substance that is difficult to wet with solder is performed by ion plating, sputtering, or vacuum deposition, and that the thickness of the coating is 10 μm or less.

[Operation] Stainless steel, heat-resistant steel, and iron-based super heat-resistant alloy as base materials are cheaper than tungsten and have good workability, so soldering jig members can be manufactured at low cost and with high precision.

The parts that come into contact with the melting solder are Ti, Zr, and A1.
, Si, B oxides, nitrides, carbides, carbonitrides, borides, Mo, W, or their alloys, which are difficult to wet with solder, so that solder does not adhere to the jig members. The above-mentioned coating also has excellent corrosion resistance against acids, so it is resistant to corrosion by flux, paste, etc., and can be used repeatedly. In addition, the base material stainless steel, heat-resistant steel, or iron-based super heat-resistant alloy itself has good corrosion resistance, so even if cracks occur in the coating during use.

The base metal will not rapidly corrode due to flux etc.

The coating in the present invention includes TiN, ZrN, BN, Al2
It is not particularly limited as long as it is a substance that does not get wet with solder, such as O, Sin, W, or Mo.

From the viewpoints of adhesion, abrasion resistance, film formability, etc., TiN is preferably used as the coating, and by setting the six-sided roughness to 3 μm or less, local adhesion of solder can be prevented.

When we investigated the cause of localized adhesion on conventional tungsten rods, we found that flux residue was trapped in sharp, deep defects such as processing scratches, and this was used as a starting point for soldering onto the surface of the tungsten rod, where solder should not have wetted. It has been clarified that adhesion occurs.

That is, setting the surface roughness to 3μ or less has the effect of preventing local adhesion of solder. moreover.

By covering one surface with the above-mentioned thin film, these deep and sharp defects are further smoothed, and the effect of preventing local adhesion of solder is further improved. Thin film coating is performed by ion plating, sputtering or vacuum deposition.

The surface quality of the film is good, the film thickness is uniform, and it has better solder adhesion resistance. Also, the thickness of the coating is 10μ
If the thickness exceeds 10 μm, the coating becomes easy to peel off, so a thickness of 10 μm or less is desirable.

〔Example〕

Next, the present invention will be explained in detail with reference to examples.

2 and 5 having the base material, surface coating, and surface roughness shown in Table 1
Three types of test rods of 1φX8Qm+Q were made.

A solder adhesion test was conducted by sequentially repeating flux application, 10 seconds of solder bathing, water washing, and drying. Note that the temperature of the solder bath was 250°C.

As can be seen from Table 1, with the conventional commercially available tungsten rod, local adhesion of solder occurred on the surface of the rod after approximately 40 repeated treatments. However, the base material is 5tlS3
04 round bar coated with 2-3μ TiN on one surface by ion plating method (surface roughness 0°8μ), and A286 round bar whose base material is Fe-based super super heat-resistant alloy with 2-3μ TiN coated on the surface.
No solder adhesion was observed in any of the products of the present invention (surface roughness 2.5μ) coated with ~3 μm of TiN by ion plating even after repeated processing 300 times.

As a result of using the soldering jig member of the present invention as the lower and upper support rods during IC soldering, no adhesion of solder occurs as described above, and it is possible to repeatedly use the soldering jig member as a support rod. It was also confirmed that the quality of the soldered IC was good.

Table 1 〔Effect of the invention〕

Claims (1)

[Scope of Claims] 1. The base material is stainless steel, heat-resistant steel, or iron-based super heat-resistant alloy, and the surface roughness of at least the portion of the base material that comes into contact with the melting solder is 3μ or less, and the base material is not wet with the solder. A soldering jig member characterized by being coated with a difficult material. 2 Substances that are difficult to wet with solder include Ti, Zr, Al, and Si.
, B oxides, nitrides, carbides, carbonitrides, borides, Mo, W, or alloys thereof. Jig parts. 3 Substances that are difficult to wet with solder are ion plating,
The soldering jig member according to claim 1 or 2, which is formed by either sputtering or vacuum deposition. 4. The soldering jig member according to any one of claims 1 to 3, wherein the coating thickness of the substance that is difficult to wet with solder is 10 μm or less.