CN101992364B - Environment-friendly lead-containing solder capable of inhibiting lead from volatilizing at high temperature in electronic industry - Google Patents

Abstract

Translated fromChinese

发明提供了一种电子行业使用的能抑制铅在高温下挥发的环保型的含铅钎料，其由以下质量百分比的组分组成：Ag0～4.0wt%，Sb0～3.0wt%，和Ni、Al、Bi、Ga、In、P、Ti中之一种或多种，每种元素的量为0.0001%-0.2%，余量为Sn和Pb。其中Ni、Al、Bi、Ga、In、P、Ti等元素的总量至多不超过0.3wt%，并有多种较好的组合，如Ni、P组合，Ni、P和Ti组合，Ni、P和Ga组合，或只选择Ni、Al等。本发明的钎料在熔化以后能自发生成一层表面改性膜，显著抑制高温下铅的挥发，在使用过程中环境条件好，对操作人员健康无影响，使用安全方便，而且成本低，因此，该钎料是电子产品绿色制造使用的新一代微连接材料。The invention provides an environmentally friendly lead-containing solder used in the electronics industry that can inhibit the volatilization of lead at high temperatures. It is composed of the following components in mass percentages: Ag0-4.0wt%, Sb0-3.0wt%, and Ni, One or more of Al, Bi, Ga, In, P, Ti, the amount of each element is 0.0001%-0.2%, and the balance is Sn and Pb. Among them, the total amount of Ni, Al, Bi, Ga, In, P, Ti and other elements does not exceed 0.3wt% at most, and there are many good combinations, such as Ni, P combination, Ni, P and Ti combination, Ni, Combination of P and Ga, or only Ni, Al, etc. The brazing material of the present invention can spontaneously form a layer of surface modified film after melting, significantly inhibit the volatilization of lead at high temperature, the environmental conditions are good during use, it has no effect on the health of operators, it is safe and convenient to use, and the cost is low, so , the solder is a new generation of micro-connection materials used in the green manufacturing of electronic products.

Description

The environment-friendly type solder containing lead that the inhibition lead that a kind of electron trade is used at high temperature volatilizees

The present invention is that application number is dividing an application of 200810069745.8 application for a patent for invention.

Technical field

The present invention relates at high temperature the volatilize solder containing lead of contaminated environment of inhibition lead that electron trade uses.

Background technology

For a long time, solder containing lead is widely used as the electronics brazing material with its cheap cost and excellent performance.Because plumbous have pollution to environment, the world has begun the unleaded research of electronic brazing filler metal from the nineties in 20th century, but up to now, the lead-free brazing that does not find all the time a kind of combination property and Sn-Pb solder to match in excellence or beauty does not find the comprehensive solution that substitutes Pb yet.In many electronic equipments, because of the reliability of lead-free brazing can not be guaranteed be difficult to real realize unleaded.Therefore, following electronic brazing filler metal will form general layout leaded and unleaded and that deposit.

Solder containing lead is that the serious harm people's is healthy, even causes operating personnel's lead poisoning because plumbous boiling point lower (1751 ℃) at high temperature can produce plumbous volatilization and contaminated air to one of pollution channel of environment.In order to improve workshop condition, the method one that generally adopts at present is to use lead-free brazing, the 2nd, establish the gas skirt exhausting on the top of soldering station.Although the former can fundamentally eliminate plumbous pollution, it is high that the lead-free brazing that uses exists fusing point, and brazing property is poor, need to use the high activity brazing flux and cause secondary pollution, and the defective such as price is high, waste is large; Although the latter can improve the air quality of electronic product production workshop, avoid operating personnel's lead poisoning, can cause severe contamination to atmosphere.How could both improve the soldering quality of connection, to avoid again the pollution in the brazing process, both at home and abroad the solution that makes the best of both worlds of neither one still so far.Prevent the report of plumbous volatilization about other field, for example Chinese patent ZL90107046 has reported a kind of plumbous liquid surface dopant, the method adopts the mixture of many oxide to cover the effusion that suppresses plumbous steam on the plumbous liquid surface, and airborne lead fume concentration is reduced.This coverture is mainly used in the patenting of steel wire and processes, and uses and be not suitable for the electronics soldering.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art, the solder containing lead of the extremely low environment-friendly type easy to use of a kind of at high temperature self plumbous vapour pressure is provided.

The solder containing lead of plumbous volatilization is comprised of the component of following mass percent under the inhibition high temperature that the present invention proposes: Ag0～4.0wt%, Sb0～3.0wt%, with among Ni, Al, Bi, Ga, In, P, the Ti one or more, the amount of every kind of element is 0.0001%-0.2%, and surplus is Sn and Pb.This solder is further characterized in that, the total amount of the elements such as Ni, Al, Bi, Ga, In, P, Ti is no more than 0.3wt% at the most in described solder.

The selection of the elements such as Ni, Al, Bi, Ga, In, P, Ti has following several preferably combination in the solder:

The one, select: Ni 0.005-0.2%, P0.001-0.1% make up, and can reach the effect that is difficult to detect plumbous volatilization in soldering.

The 2nd, select: Ni 0.005-0.2%, P0.001-0.1% and Ti0.0001-0.005% make up, and can reach the effect that is difficult to detect plumbous volatilization in soldering.

The 3rd, select: Ni 0.005-0.2%, P0.001-0.1% and Ga 0.0001-0.005% make up, and can reach the effect that is difficult to detect plumbous volatilization in soldering.

The 4th, select: Al 0.005-0.2%, Ni 0.001-0.01% and Ga 0.0001-0.005% combination can reach the effect that is difficult to detect plumbous volatilization in soldering.

The 5th, select: Al 0.005-0.2%, Bi 0.001-0.2% and In 0.0001-0.005% combination can make plumbous volatile quantity significantly descend.

The 6th, only select Ni 0.005-0.2%, plumbous volatile quantity is significantly reduced or be difficult to detect plumbous volatilization.

The 7th, only select Al 0.005-0.2%, plumbous volatile quantity is significantly descended.

Why the solder of the present invention's design can suppress volatilization plumbous under the high temperature, is because it can spontaneous generation layer of surface Modified Membrane after fusing.Because this solder is dispersed in the surface modification elements such as micro-Ni, Al, Bi, Ga, In, P, Ti in the brazing filler metal alloy, after solder fusing, according to Gibbs adsorption equation:

Wherein: Γ represents adsorbance, and C represents concentration, and R is gas constant, and T is thermodynamic temperature,

Be illustrated in constant temperature lower surface tension force with the rate of change of concentration.

When

＜0 o'clock, Γ＞0, be positive absorption this moment.Namely originally being dispersed in inner micro-surface modification element will make surface concentration greater than inner concentration from the trend apparent motion, and form fine and close Modified Membrane on the surface.

On the liquid solder surface, plumbous vapour pressure can be expressed as

At a certain temperature, the saturated vapour pressure of pure leadBe definite value.Therefore, the size of plumbous vapour pressure depends primarily on activity coefficient plumbous in the liquid solder skin covering of the surface under brazing temperatureAnd molar fraction

When the modifying element in the molten solder is adsorbed to the surface, can not only reduce molar fraction plumbous in the skin covering of the surface

, and can reduce activity coefficient plumbous in the skin covering of the surface

Owing to the compactness of formed Modified Membrane, can significantly reduce plumbous diffusion velocity by oxide-film, thereby stop that lead atom is to the transfer on surface simultaneously.Therefore can significantly suppress exposure and the volatilization of lead in the liquid solder under the high temperature.

As seen, the remarkable advantage of solder of the present invention is under the prerequisite that keeps the solder containing lead function admirable, can suppress volatilization plumbous under the high temperature, in use environmental condition is good, without impact, safe and convenient to use on operator ' s health, and cost is low, therefore, this solder is of new generation little connecting material that the electronic product green manufacturing is used.

The specific embodiment

Embodiment 1: be that the Pb of Sn, the 370g of 630g places and carries out refinement oxide and boiling refining in the open type electric furnace with quality; then inject sealed stove; add Al 0.5g and Ni 0.01g, Ga 0.005g and carry out the modification refining; the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, record plumbous volatile quantity than Sn-37Pb 65 % that descend.

Embodiment 2: be that the Ag of Pb, 20g of Sn, the 360g of 620g places and carries out refinement oxide and boiling refining in the open type electric furnace with quality; then inject sealed stove; add Al 0.1g and Bi 1.5g, In 0.05g and carry out the modification refining; the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, record plumbous volatile quantity than Sn-37Pb 72 % that descend.

Embodiment 3: be that the Sb of Pb, 20g of Sn, the 430g of 550g places and carries out refinement oxide and boiling refining in the open type electric furnace with quality; then inject sealed stove; add Ni 0.5g and P 0.05g, Ti 0.005g and carry out the modification refining; the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, be difficult to detect plumbous volatilization.

Embodiment 4: change the interpolation element of embodiment 1 into Ni 0.1g and Ga 0.01g, P 0.05g, the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, has been difficult to detect plumbous volatilization.

Embodiment 5: change the interpolation element of embodiment 1 into Ni 0.1g and P 0.05g, the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, has been difficult to detect plumbous volatilization.

Embodiment 6: change the interpolation element of embodiment 1 into Ni 0.12g, the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, has been difficult to detect plumbous volatilization.

Embodiment 7: change the interpolation element of embodiment 2 into Al 0.1g and carry out the modification refining, the gained solder is heated to 800 ℃ with 10 ℃ of per minutes under protective atmosphere, records plumbous volatile quantity than Sn-37Pb 62 % that descend.

Claims (1)

Translated fromChinese

1.一种电子行业使用的抑制铅在高温下挥发的环保型含铅钎料，其包含以下质量百分比的组分：Sb0～3.0wt%，Ni 0.005-0.2%、P0.001-0.1%和Ga 0.0001-0.005%，余量为Sn和Pb。1. An environment-friendly lead-containing solder used in the electronics industry to suppress the volatilization of lead at high temperatures, which comprises the following components in mass percentages: Sb0～3.0wt%, Ni 0.005-0.2%, P0.001-0.1% and Ga 0.0001-0.005%, the balance is Sn and Pb.