CN1203960C - Oxidation-inhibited lead-free welding materials - Google Patents
Oxidation-inhibited lead-free welding materials Download PDFInfo
- Publication number
- CN1203960C CN1203960C CN 03110895 CN03110895A CN1203960C CN 1203960 C CN1203960 C CN 1203960C CN 03110895 CN03110895 CN 03110895 CN 03110895 A CN03110895 A CN 03110895A CN 1203960 C CN1203960 C CN 1203960C
- Authority
- CN
- China
- Prior art keywords
- lead
- scolder
- solder
- present
- free solder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Abstract
The present invention relates to lead-free solder with oxidation resistance, which relates to a solder composition, particularly to a lead-free solder composition. The present invention has the following chemical constituents by the weight percentage: 0.54 to 5 of Ag, 0 to 2 of Cu, 0.001 to 1 of P, and the rest of Sn; 0.01% to 1% (solder WT) of La, Ce and mischmetal Re can be added in the solder. The solder of the present invention does not has Pb. Compared with the existing Sn-Ag-Cu solder alloy, the present invention has superior characteristics on the solidification structure, the mechanical properties, and the creep fatigue preventing characteristic of the solder. The present invention solves the problem that the oxidation resistance of the existing lead-free solder is low.
Description
Technical field:
The present invention relates to a kind of solder composition, particularly a kind of Pb-free solder compositions.
Background technology:
At present, the typical solders that is used for electronic industry Electronic Packaging and assembling is the Sn-Pb alloy.Though the Sn-Pb alloy has characteristics such as excellent wettability and weldability, electroconductibility, mechanical property, cost are lower, Pb and contain the hazardous and noxious substances that the Pb thing is the healthy and contaminate environment of harm humans.Along with being gradually improved of legislations of environmental protection; ban use of plumbous cry surging day by day; Japan, European Union and the U.S. have all worked out the unleaded standard of scolder of oneself in succession; wherein Japanese enterprises has been brought into use lead-free solder in its product, and the European Community then proposes requirement in 2008 and all uses lead-free solders in the COST of last year leadless welding alloy research project.Therefore, in electronic industry, need a kind of unleaded welding flux alloy to replace traditional Sn-Pb welding flux alloy.Sn-Ag-Cu is that alloy has application promise in clinical practice in current lead-free solder, has obtained the recommendation of U.S. NEMI (National Electronics Manufacturing Initiative), Britain DTI (Department of Trade and Industry), Soldertec (The Solder TechnologyCenter) etc.Based on Sn-Ag-Cu system, United States Patent (USP) 4,778,733 propose the lead-free solder by Sn-Ag (0.05-3%)-Cu (0.7-6%) forms; United States Patent (USP) 5,527,628 have narrated the alloy that consists of 93.6Sn-4.7Ag-1.7Cu; United States Patent (USP) 5,863,493 have provided Sn-Ag (2.0-5.0%)-Cu (0-2.9%) lead-free solder.United States Patent (USP) 4,758 in addition, and 407 add element Ni on Sn-Ag (0-5.0%)-Cu (3.0-5.0%) basis; United States Patent (USP) 6,179,935 are added micro-Ni and Ge on Sn-Ag (0-4.0%)-Cu (0-2.0%) basis.For Sn-Ag-Cu is scolder, and its over-all properties is more superior, but its wettability is relatively poor, and alloy structure is thick, skewness.On the other hand, because the content of Sn is in use compared the generation that can increase metal oxide greatly with traditional Sn-37Pb scolder up to more than the 90 weight % in the Sn-Ag-Cu series lead-free solder alloy.Though in Chinese patent CN1332057A, provided the lead-free solder that contains rare earth element, owing to the existence of a large amount of Sn, made the resistance of oxidation of scolder reduce equally in the scolder by adding rare earth elements RE.Narrated the lead-free solder of a kind of Sn-Ag-Cu-P of consisting of among the JP2002-336988A, owing in electron trade, there are many application scenarios to need the temperature of molten solder to be higher than 300 degree, immersed solder as the components and parts pin, the temperature of molten solder generally reaches the 350-400 degree, at this moment P or Ge lose oxidation resistant effect fully, have reduced the resistance of oxidation of solder.
Summary of the invention:
The invention provides a kind of lead-free solder with resistance of oxidation, it has solved the low problem of resistance of oxidation that existing lead-free solder exists.Lead-free solder of the present invention is made up of the chemical ingredients of following weight percent: Ag 0.5-5%, Cu 0-2%, P 0.001-1%, RE 0.01-1%, Sn surplus.Leadless welding alloy involved in the present invention does not use the lead of hypertoxicity in as the tin of the basic composition of scolder and lead, have the solderability better than existing scolder.Describe effect and the optimum content thereof that respectively adds element among the present invention: Ag below in detail and can form Sn-Ag eutectic (Sn-3.5Ag with the Sn matrix, 221 ℃) with the fusing point that reduces scolder, the mechanical property that improves scolder, especially Sn-Ag be scolder with traditional Sn-Pb eutectic phase than the creep resistance fatigue property that excellence is arranged.If the add-on of Ag is less than 0.5%, these act on just with not obvious.The Ag that adds more than 5.0% can make the liquidus temperature of welding flux alloy sharply raise, thereby causes the rising of brazing temperature to make electronic component may suffer thermal damage.Ag content is 1.0%-4.0% preferably, more preferably 3.0%-4.0%.Interpolation Cu can make and form ternary eutectic between Sn-Ag-Cu to reduce the fusing point of scolder.The Cu element can also improve the wettability that Sn-Ag is a scolder.The existence of Cu element also can improve the intensity of scolder to remedy this shortcoming of Sn-Ag scolder undercapacity.The Sn-Ag-Cu eutectic solder also has higher intensity.And when the mode by immersed solder in fused scolder pot, on the printed circuit board (PCB) that is covered with the Copper Foil lead during soldering electronic component, the Cu that exists in the fusion welding pot has the copper that suppresses in the Copper Foil lead additional effect to the diffusion of fusion welding pot.The preferably 0.1%-2.0% of copper content, more preferably 0.1%-1.0%.Owing to not leaded the contain a large amount of tin (reach 90% or more) of the present invention, when using, reality can therefore increase the generation of scolder pot fusion welding surface metal oxide with Ag and Cu element generation.Therefore, the element P that is added with 0.001%-1% can stop the oxidation of welding flux alloy effectively, because the surface action of element P, the upper surface of molten braze alloy forms one deck very thin films in the scolder pot, by the oxidizing reaction that takes place at solder surface:
SnO+P
2O
5→SnO·P
2O
5
Can hinder welding flux alloy directly and being in contact with one another of ambient air.On the other hand, the existence of elements A g and Cu has also promoted this surface action of P in the scolder, thereby prevents the further oxidation of solder surface.If the add-on of element P is less than 0.001%, this anti-oxidation effect is just not obvious, adds the solderability of the element P meeting deterioration welding flux alloy more than 1%.When adding P, P content preferably 0.005%-0.5%, more preferably 0.005%-0.1% in alloy.Also add the proper amount of rare-earth elements RE among the present invention improving the tissue of scolder,, the tissue of scolder is played a part metamorphic homogenization, thereby improve the mechanical property of welding flux alloy because the RE element can promote the forming core of scolder in process of setting.The adding of RE can also significantly improve scolder creep resistance fatigue property.If RE content is less than 0.01%, its effect is just not obvious, adds 1% above RE and can make the solder performance variation, and fusing point raises.When adding RE, the preferably 0.05%-0.5% of RE content in alloy.According to the effect of above each composition, scolder of the present invention does not contain Pb, compare with existing Sn-Ag-Cu welding flux alloy, and still be all to have shown superior characteristic aspect the creep resistance fatigue characteristic of scolder in solidified structure, the mechanical property of scolder.Lead-free solder of the present invention with above-mentioned composition can be smelted by traditional method, and promptly Sn, Ag, Cu are with the raw metal supply, and RE and element P then require to add by the form with master alloy, heating and stirring in crucible, and casting can obtain welding flux alloy.Welding flux alloy of the present invention can be processed to form the form of soldering tin bar, scolding tin rod, soldering tin wire, solder ball and soldering paste etc. by traditional technology, thereby can satisfy needed welding flux alloys such as PCB assembling, SMT microelectronics surface encapsulation and surface mount.The object of the present invention is to provide a kind of leadless welding alloy, add mishmetal RE (mixture of La and Ce) and element P.Because the tissue of Sn-Ag-Cu scolder mainly reaches eutectic phase mutually by rich Sn and forms, adding RE can make the thick rich Sn in the alloy graining tissue be inhibited mutually, promptly by metamorphism to the scolder solidification and crystallization process by using, realize the homogenizing of solidified structure, thereby improve the mechanical property and the creep resistance fatigue characteristic of welding flux alloy; Addition element P, the surface action that the P element is presented in fused scolder pot can reduce the generation of scolder pot surface metal oxide, the fraction defective when reducing the welding of PCB circuit card.
Embodiment:
Embodiment one: the lead-free solder of present embodiment is made up of the composition of following weight percent: Ag 3.5, Cu 0.7, P 0.01, Sn surplus.
Embodiment two: the lead-free solder of present embodiment is made up of the composition of following weight percent: Ag 3.5, Cu 0.7, P 0.05, Sn surplus.
Embodiment three: the lead-free solder of present embodiment is made up of the composition of following weight percent: Ag 3.5, Cu 0.7, P 0.05, RE 0.1, Sn surplus.
Embodiment four: the lead-free solder of present embodiment is made up of the composition of following weight percent: Ag 3.5, Cu 0.7, P 0.05, RE 0.4, Sn surplus.
Now with the lead-free solder contrast (see Table 1) of traditional lead-free solder (containing Ag3.5%, Cu0.7%, Sn95.8%) with above-mentioned embodiment one to four:
Table 1 is the contrast of embodiment of the present invention and traditional SnAgCu lead-free solder
| Alloying constituent (weight %) | Fusing point (℃) | The rate of spread (%) | ||||||
| Sn | Ag | Cu | P | RE | Solidus curve | Liquidus line | ||
| Embodiment one | 95.79 | 3.5 | 0.7 | 0.01 | 215 | 224 | 81.46 | |
| Embodiment two | 95.75 | 3.5 | 0.7 | 0.05 | 215 | 223 | 76.59 | |
| Embodiment three | 95.65 | 3.5 | 0.7 | 0.05 | 0.1 | 217 | 225 | 77.61 |
| Embodiment four | 95.35 | 3.5 | 0.7 | 0.05 | 0.4 | 215 | 222 | 83.03 |
| Conventional case | 95.8 | 3.5 | 0.7 | 217 | 218 | 79.97 | ||
In addition, for observe in traditional Sn-3.5Ag-0.7Cu scolder add element P and RE to scolder in the influence of Cu plate wettability of the surface, above-mentioned embodiment and conventional case welding flux alloy have been carried out wettability test, the results are shown in Table 1.Discovery wettability influence to scolder under the situation of adding a small amount of P and RE is little, but when content of rare earth was higher, as enforcement mode three, welding flux alloy slightly improved than the conventional case scolder in the rate of spread on Cu plate surface.Again embodiment of the present invention and conventional case have been carried out the antioxidant property test, be about to scolder and be incubated the burn out rate that 17.5h observes scolder under 280 ℃ of temperature, concrete test-results sees Table 1.Therefrom in traditional SnAgCu (comparative example), add the antioxidant property that element P (embodiment 1 and embodiment 2) can obviously strengthen scolder as can be seen, especially at P content under 0.01% condition; The resistance of oxidation of scolder reduces when P content is higher on the contrary, but still will be higher than the conventional case of not adding element P.Adding under the situation of rare earth, when content of rare earth was low, P also had remarkable effect to the antioxidant property that strengthens scolder, but when content of rare earth is higher, though at this moment when interpolation element P the resistance of oxidation of scolder also to be lower than traditional SnAgCu lead-free solder.
Table 2 is comparisons of embodiment of the present invention and traditional SnAgCu lead-free solder antioxidant property
| Former weight (g) | Residuals weight (g) | Scaling loss amount (g) | Burn out rate (%) | Soaking time (h) | Holding temperature (℃) | |
| Embodiment one | 31.38 | 31.3124 | 0.0676 | 0.215 | 17.5 | 280 |
| Embodiment two | 31.38 | 31.1213 | 0.2587 | 0.824 | 17.5 | 280 |
| Embodiment three | 31.38 | 31.1629 | 0.2171 | 0.692 | 17.5 | 280 |
| Embodiment four | 31.38 | 29.3445 | 2.0355 | 6.487 | 17.5 | 280 |
| Conventional case | 31.38 | 30.7687 | 0.6113 | 1.948 | 17.5 | 280 |
Claims (5)
1, the lead-free solder that has resistance of oxidation is characterized in that it is made up of the chemical ingredients of following weight percent: Ag 0.5-5%, Cu 0-2%, P 0.001-1%, RE 0.01-1%, Sn surplus.
2, the lead-free solder with resistance of oxidation according to claim 1 is characterized in that the content of Ag in scolder is the 1%-4% of scolder weight.
3, the lead-free solder with resistance of oxidation according to claim 1 is characterized in that the content of Cu in scolder is the 0.1%-2% of scolder weight.
4, the lead-free solder with resistance of oxidation according to claim 1 is characterized in that the content of P in scolder is the 0.005%-0.5% of scolder weight.
5, the lead-free solder with resistance of oxidation according to claim 1 is characterized in that at the content of RE in scolder be the 0.05%-0.5% of scolder weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03110895 CN1203960C (en) | 2003-01-15 | 2003-01-15 | Oxidation-inhibited lead-free welding materials |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03110895 CN1203960C (en) | 2003-01-15 | 2003-01-15 | Oxidation-inhibited lead-free welding materials |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1439480A CN1439480A (en) | 2003-09-03 |
| CN1203960C true CN1203960C (en) | 2005-06-01 |
Family
ID=27796785
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03110895 Expired - Lifetime CN1203960C (en) | 2003-01-15 | 2003-01-15 | Oxidation-inhibited lead-free welding materials |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1203960C (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080246164A1 (en) * | 2004-06-01 | 2008-10-09 | Minoru Ueshima | Soldering Method, Solder Pellet for Die Bonding, Method for Manufacturing a Solder Pellet for Die Bonding, and Electronic Component |
| US7335269B2 (en) | 2005-03-30 | 2008-02-26 | Aoki Laboratories Ltd. | Pb-free solder alloy compositions comprising essentially Tin(Sn), Silver(Ag), Copper(Cu), and Phosphorus(P) |
| CN100494436C (en) * | 2005-08-02 | 2009-06-03 | 马莒生 | Low melting point leadless welding flux alloy |
| EP1749616A1 (en) * | 2005-08-05 | 2007-02-07 | Grillo-Werke AG | Process for arc or beam soldering or welding of workpieces from same or different metal or metallic aloys using a Sn-Basis alloy filler; Wire of Tin-basis alloy |
| CN103028862B (en) * | 2011-09-29 | 2015-08-26 | 江苏天瑞仪器股份有限公司 | For mass spectrometric six grades of bars being welded on solder flux on fixed head and technique |
| CN102581514B (en) * | 2012-03-16 | 2015-06-03 | 金华市金钟焊接材料有限公司 | Silver solder containing phosphorus, stannum and rare earth |
| CN103273217B (en) * | 2013-05-29 | 2016-01-13 | 哈尔滨工业大学深圳研究生院 | High reliability solder of a kind of local strengthening and preparation method thereof |
| CN103586600A (en) * | 2013-11-12 | 2014-02-19 | 宁波市鄞州恒迅电子材料有限公司 | Lead-free soldering tin alloying pellet |
| CN105834611B (en) * | 2016-05-04 | 2018-02-13 | 中南大学 | A kind of high conductance high reliability Ce Sn Ag Cu solders suitable for Electronic Packaging |
| CN113416866A (en) * | 2021-06-29 | 2021-09-21 | 南京青锐风新材料科技有限公司 | Lead-free solder oxidation resistant alloy and production and preparation process thereof |
| CN114055012A (en) * | 2021-11-05 | 2022-02-18 | 安徽工业大学 | Multi-element copper-based alloy brazing filler metal containing rare earth elements, preparation method and brazing method thereof |
-
2003
- 2003-01-15 CN CN 03110895 patent/CN1203960C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CN1439480A (en) | 2003-09-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102936669B (en) | Low-melting-point lead-free solder alloy | |
| CN108971793B (en) | Low-temperature lead-free solder | |
| KR19980068127A (en) | Lead-Free Alloys for Soldering | |
| CN101716702B (en) | Multi-component alloy cadmium-free low-silver solder | |
| CN103341699A (en) | Unleaded Sn-In-Ag brazing filler metal replacing tin-lead brazing filler metal | |
| US20070172381A1 (en) | Lead-free solder with low copper dissolution | |
| CN101269446A (en) | Sn-Zn-Ga-Ce leadless brazing filler metal | |
| CN101348875A (en) | Tin, bismuth and copper type low temperature lead-free solder alloy | |
| CN1203960C (en) | Oxidation-inhibited lead-free welding materials | |
| CN101716705B (en) | Multi-alloy cadmium-free phosphor-free copper-based solder | |
| CN101537546B (en) | Sn-Ag-Cu lead-free solder containing Pr, Ni and Ga | |
| CN101585119A (en) | Oxidation resistant lead-free solder alloy in low silver | |
| CN100467192C (en) | Pb-free solder alloy compositions comprising essentially tin, silver, copper and phosphorus | |
| CN101579790B (en) | Sn-Ag-Cu lead-free solder containing Nd, Li, As and In | |
| CN101081463A (en) | Sn-Ag-Cu-Dy Lead-free solder alloy | |
| CN1313631C (en) | Tin silver copper nickel aluminium series leadless welding flux alloy | |
| CN1239290C (en) | Leadless soft brazing alloy for wave crest soldering | |
| CN102500946A (en) | Sn-Ag-Cu-Bi-Er low-silver and lead-free welding flux and preparation method for same | |
| CN111940945A (en) | Sn-Zn-In-Ga lead-free solder and preparation method thereof | |
| CN101537547B (en) | Sn-Ag-Cu lead-free solder containing Nd, Ni and Co | |
| CN101579789B (en) | Sn-Ag-Cu lead-free solder containing Pr, Zr and Co | |
| CN101564803A (en) | Leadless solder of silverless Sn-Bi-Cu system and preparation method thereof | |
| CN101733575A (en) | Tin-zinc-bismuth-copper leadless solder with low cost and welding spot thereof | |
| JP2001287082A (en) | Solder | |
| CA2540486A1 (en) | Pb-free solder alloy compositions comprising essentially tin (sn), silver (ag), copper (cu), nickel (ni), phosphorus (p) and/or rare earth: cerium (ce) or lanthanum (la) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of invention: Lead free solder with oxidation resistance Effective date of registration: 20210409 Granted publication date: 20050601 Pledgee: Shenzhen small and medium sized small loan Co.,Ltd. Pledgor: YIK SHING TAT INDUSTRIAL Co.,Ltd. Registration number: Y2021980002513 |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20050601 |