KR20040090273A

KR20040090273A - Lead-free solder alloy

Info

Publication number: KR20040090273A
Application number: KR1020030024317A
Authority: KR
Inventors: 윤원규; 김관수
Original assignee: 희성금속 주식회사
Priority date: 2003-04-17
Filing date: 2003-04-17
Publication date: 2004-10-22

Abstract

PURPOSE: A lead-free solder alloy is provided to prevent workers from being subject to lead poisoning due to lead contained in a solder alloy by performing soldering work using the lead-free solder alloy. CONSTITUTION: A lead-free solder alloy includes 0.01 to 7.0 weight percent of Cu, 0.01 to 3.0 weight percent of Ge, and Sn. Sn has no poisonous component and provides wetness to a base metal so that Sn is an essential metal for soldering work. Cu is added to a lead-free alloy in order to improve bonding strength while preventing electronic parts or a printed circuit board from being eroded. Instead of Ge, it is possible to use one selected from the group consisting of Ag, Ga, In or a mixture thereof. Ag allows a melted lead-free alloy to rapid diffused into the base metal, thereby improving bonding strength between the lead-free alloy and the base metal.

Description

Lead-free solder alloy

본 발명은 납땜용 무연합금에 관한 것으로서, 납을 함유하지 않는 합금에 의해 납땜이 이루어지도록 하여 납의 중독 등에 의한 피해를 방지하도록 된 납땜용 무연합금에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead-free alloy for soldering, and relates to a lead-free alloy for soldering to prevent damage caused by poisoning of lead by performing soldering with an alloy containing no lead.

일반적으로 납땜은 땜납을 용융하여 금속을 접합시키므로 접합할 금속보다 용융온도가 낮은 금속이 사용되는데, 납의 용융온도(327℃)보다 낮은 온도에서 용융되는 연납과, 용융온도가 대체적으로 450℃ 이상인 경납으로 대별된다.In general, soldering melts solder to bond metals, and therefore, metals having a lower melting temperature than metals to be joined are used, such as solders that are melted at a temperature lower than the melting temperature of lead (327 ° C) and light solders having a melting temperature of generally 450 ° C or higher. It is roughly divided into.

연납의 성분은 납과 주석이며, 그 함유량에 따라서 인장강도 및 전단강도가 각각 다르게 나타나게 된다.The lead components are lead and tin, and the tensile strength and shear strength are different depending on the content.

한편 경납은 분말, 밴드, 와이어 등의 형상으로 형성되며, 구리(Cu).아연(Zn), 납(Pb)이 주성인 황동납과 은(Ag)을 첨가하여 유동성을 개선한 은납 등이 사용된다.On the other hand, braze is formed in the form of powder, band, wire, etc., and copper (Cu), zinc (Zn), and lead (Pb) are mainly used for brass lead and silver (Ag) to improve flowability. do.

그러나 납은 분해되지 않는 금속이므로 일단 인체내에 섭취되면 방출되지 않고 축적되는데, 납땜 작업시 땜납의 용융으로 발생되는 가스 등에 작업자가 노출되면 호흡기를 통해 인체에 축적되어 납중독이라는 인체에 치명적인 영향을 미치는문제점들이 있었다.However, lead is a metal that does not decompose, and when it is ingested in the human body, it is not released and accumulates. When a worker is exposed to a gas generated by the melting of solder during soldering, it accumulates in the human body through a respiratory organ and has a fatal effect on the human body called lead poisoning. There was.

본 발명은 이와같은 종래의 문제점들을 해결하기 위해 발명된 것으로서, 땜납의 성분중 납을 포함하지 않고도 납땜이 이루어지도록 하여 납에 의해 인체가 입는 피해를 예방하기 위해 무연 합금을 제공하는데, 특히 이러한 무연합금에 미량함유된 금속, 즉 불순물에 의해 무연합금의 성질이 크게 영향을 받고 그 함유량에 따라서 상당한 차이가 있다. 따라서 본 발명은 주석(Sn)을 기본물질로 하고 여기에 물리적 및 기계적 특성을 증대시키기 위해 부가금속으로 구리(Cu), 갈륨(Ga), 은(Ag), 게르마늄(Ge), 인듐(In)을 첨가하여 조성되는 것을 특징으로 한다.The present invention has been invented to solve such a conventional problem, to provide a lead-free alloy in order to prevent the damage to the human body by the lead so that the solder is made without including lead in the solder component, in particular, such a lead-free The properties of lead-free alloys are greatly affected by the metals, i.e. impurities, contained in the alloys, and there are significant differences depending on their contents. Therefore, the present invention is based on tin (Sn), and in order to increase the physical and mechanical properties therein, copper (Cu), gallium (Ga), silver (Ag), germanium (Ge), indium (In) It is characterized by being added to the composition.

본 발명에 따르면, 무연 Sn-Cu 납땜 계열이 제공된다. 상기 납땜들은 낮은 고상선 온도를 특징으로 한다.According to the present invention, a lead-free Sn-Cu solder series is provided. The solders are characterized by low solidus temperature.

본 발명의 바람직한 실시양태에서 낮은 고상선 온도나 다성분 납땜합금은 대부분 Sn 및 Cu와 물리적 및 기계적 특성을 증대시키는 효과량의 제 3성분을 갖는다.In a preferred embodiment of the present invention, the low solidus temperature or multicomponent braze alloy has mostly Sn and Cu and an effective amount of a third component that enhances the physical and mechanical properties.

주석(Sn)은 자체 독성이 없고 접합모재에 대하여 젖음성을 제공하는 역할을 하는 땜납기재의 필수 금속이다.Tin (Sn) is an essential metal of the solder base which does not have its own toxicity and serves to provide wettability to the bonded base material.

구리(Cu)는 무연합금에 첨가되어 합금의 조직을 미세화하여 접합강도를 향상시키는 동시에 전자부품이나 인쇄회로기판의 침식을 억제하는 역할을 하며 본 발명의 실시예에는 0.01 ~ 7.0 중량%가 함유되고 구리함유량이 0.01중량% 미만이면 저융점화의 효과가 미미하게 되고 7.0 중량%를 초과할 경우에는 융점의 응고범위가 넓어지게 된다.Copper (Cu) is added to the lead-free alloy to refine the structure of the alloy to improve the bonding strength and at the same time serves to suppress the erosion of electronic components or printed circuit boards in the embodiment of the present invention contains 0.01 to 7.0% by weight When the copper content is less than 0.01% by weight, the effect of low melting point becomes insignificant, and when it exceeds 7.0% by weight, the solidification range of the melting point becomes wider.

물리적 및 기계적 특성을 증대시키는 제 3성분은 Ag, Ge, Ga, In 또는 이들 성분들 모두의 혼합물일 수 있다.The third component which enhances the physical and mechanical properties may be Ag, Ge, Ga, In or a mixture of all of these components.

본 발명의 특히 바람직한 예에서 고상선을 강하시키는 제 3성분은 Ge이다. 하나의 Sn-Cu-Ge 합금 조성물은 0.01 ~ 7.0%중량의 Cu 및 0.01 ~ 3.0%중량의 Ge을 포함하고, 나머지가 Sn으로 조성된다.In a particularly preferred embodiment of the present invention, the third component that lowers the solidus line is Ge. One Sn—Cu—Ge alloy composition comprises 0.01 to 7.0% by weight of Cu and 0.01 to 3.0% by weight of Ge, the remainder being composed of Sn.

본 발명의 또다른 실시양태으로서는 물리적 및 기계적 특성을 증대시키는 효과량의 제 3성분은 Ga이다. 하나의 Sn-Cu-Ga합금 조성물은 0.01 ~ 7.0%중량의 Cu 및 0.01 ~ 3.0%중량의 Ga을 포함하고, 나머지가 Sn으로 조성된다.In another embodiment of the present invention, the third amount of the effective amount that enhances the physical and mechanical properties is Ga. One Sn—Cu—Ga alloy composition comprises 0.01 to 7.0% by weight of Cu and 0.01 to 3.0% by weight of Ga, the remainder being composed of Sn.

본 발명의 또다른 실시양태으로서는 물리적 및 기계적 특성을 증대시키는 효과량의 제 3성분은 In이다. 하나의 Sn-Cu-In합금 조성물은 0.01 ~ 7.0%중량의 Cu 및 0.01 ~ 3.0%중량의 In을 포함하고, 나머지가 Sn으로 조성된다.In another embodiment of the invention, the third component of the effective amount to enhance the physical and mechanical properties is In. One Sn—Cu—In alloy composition comprises 0.01 to 7.0% by weight of Cu and 0.01 to 3.0% by weight of In, and the rest is composed of Sn.

본 발명의 또다른 실시양태으로서는 물리적 및 기계적 특성을 증대시키는 효과량의 제 3성분은 은(Ag)이다. 은(Ag)은 무연합금에 첨가되어 원자의 반경이 작기 때문에 무연합금의 용융중에 접합모재로의 확산속도를 빠르게 하여 무연합금과 모재합금과의 접합강도를 상승시키며 Sn-Cu-Ag합금 조성물은 0.01 ~ 7.0%중량의 Cu 및 0.01 ~ 2.0%중량의 Ag를 포함하고, 나머지가 Sn으로 조성된다. 본 발명에서는 0.01 ~ 2.0중량%가 함유되고 함유량이 0.01중량% 미만이면 무연땜납의 융점을 낮추는데 한계가 있어 기대하는 효과를 얻을 수 없으며 2.0중량% 를 초과할 경우에는 융점의 고온화 및 유동성이 너무 커져 쉽게 퍼지게 되므로 바람직하지 못하다.In another embodiment of the present invention, the third amount of the effective amount that enhances the physical and mechanical properties is silver (Ag). Since silver (Ag) is added to lead-free alloys and the radius of atoms is small, the diffusion rate of lead-free alloys into the bonding material is increased during melting of the lead-free alloys, thereby increasing the bonding strength between the lead-free alloys and the base alloy. 0.01 to 7.0% by weight of Cu and 0.01 to 2.0% by weight of Ag, with the remainder being composed of Sn. In the present invention, if the content is 0.01 to 2.0% by weight and the content is less than 0.01% by weight, there is a limit in lowering the melting point of the lead-free solder, so that the expected effect cannot be obtained. It is not desirable because it spreads easily.

이하 실시예에 따라 설명한다.It demonstrates according to an Example below.

실시예 1은 구리가 0.7중량%, 은이 2.0중량%, 나머지가 주석으로 조성된 무연합금이다.Example 1 is a lead-free alloy composed of 0.7 wt% copper, 2.0 wt% silver, and the balance tin.

실시예 2는 구리가 0.7중량%, 갈륨이 1.5중량%, 나머지가 주석으로 조성된 무연합금이다.Example 2 is a lead-free alloy composed of 0.7 wt% copper, 1.5 wt% gallium, and the balance tin.

실시예 3은 구리가 0.7중량%, 인듐이 1.0중량%, 나머지가 주석으로 조성된 무연합금이다.Example 3 is a lead-free alloy composed of 0.7 wt% copper, 1.0 wt% indium, and the remainder composed of tin.

실시예 4는 구리가 0.7중량%, 게르마늄이 1.5중량%, 나머지가 주석으로 조성된 무연합금이다.Example 4 is a lead-free alloy composed of 0.7 wt% copper, 1.5 wt% germanium, and the balance tin.

실시예 5는 구리가 0.7중량%, 갈륨이 1.5중량%, 게르마늄이 1.5중량%, 인듐이 1.0중량%, 은이 1.0중량%이고 나머지가 주석으로 조성된 무연합금이다.Example 5 is a lead-free alloy composed of 0.7 wt% copper, 1.5 wt% gallium, 1.5 wt% germanium, 1.0 wt% indium, 1.0 wt% silver and the remainder composed of tin.

상기 표에 나타난 바와 같이 본 발명의 무연합금은 액상온도가 210∼218℃이고, 고상온도는 201∼209℃이므로 무연땜납에 매우 적합함을 알 수 있으며 비교예에서의 땜납보다 융점인 고상온도 및 액상온도가 월등히 우수함을 알 수 있다.As shown in the above table, the lead-free alloy of the present invention has a liquidus temperature of 210 to 218 ° C and a solid phase temperature of 201 to 209 ° C, which makes it very suitable for lead-free solders. It can be seen that the liquid phase temperature is excellent.

또한 본 발명의 무연합금은 매끄러운 외관을 가지고 크리프강도의 증가를 나타낸다. 본 발명의 합금의 적합성을 나타내기 위해 실시예들과 주석과 구리만으로 조성된 기존합금과 파열강도 및 인장강도를 측정하였다.In addition, the lead-free alloy of the present invention has a smooth appearance and shows an increase in creep strength. In order to show the suitability of the alloy of the present invention, the conventional alloy, the bursting strength and the tensile strength of only the tin and copper were measured.

상기 표에서 알 수 있는 바와 같이 실시예의 인장강도와 파열강도는 기존합금의 인장강도보다 더 높음을 알 수 있다.As can be seen from the table, it can be seen that the tensile strength and burst strength of the embodiment are higher than the tensile strength of the existing alloy.

상술한 바와 같이 본 발명의 무연합금은 종래 Sn-Pb계 땜납에 비하여 납이 함유되어 있지 않아 작업환경을 개선시킴은 물론 환경오염을 방지하게 되고 종래 Sn-Cu계 합금에 인듐, 게르마늄, 갈륨, 은을 첨가함으로써 무연합금의 융점을 저하시키고 물리적, 기계적 특성을 증가시킬 수 있다.As described above, the lead-free alloy of the present invention does not contain lead as compared to conventional Sn-Pb-based solders, thereby improving the working environment as well as preventing environmental pollution. In the conventional Sn-Cu-based alloys, indium, germanium, gallium, The addition of silver can lower the melting point of lead-free alloys and increase their physical and mechanical properties.

또한 납을 사용하지 않고도 기존의 땜납과 거의 유사한 융점을 갖게 되므로 Sn-Pb계 땜납을 사용하던 장비를 그대로 사용할 수 있게 됨은 물론 무연합금의 사용량을 최소화하게 되므로 매우 경제적인 효과를 얻게 된다.In addition, since it has a melting point almost similar to that of the existing solder without using lead, the equipment that used the Sn-Pb-based solder can be used as it is, and the use of lead-free alloy is minimized, thereby achieving a very economic effect.

Claims

A lead-free alloy for soldering, wherein Cu is 0.01 to 7.0% by weight, Ge is 0.01 to 3.0% by weight, and the remainder is Sn.

A lead-free alloy for soldering, wherein Cu is 0.01 to 7.0% by weight, Ga is 0.01 to 3.0% by weight, and the remainder is Sn.

A lead-free alloy for soldering, wherein Cu is 0.01 to 7.0% by weight, In is 0.01 to 3.0% by weight, and the remainder is Sn.

A lead-free alloy for soldering, wherein Cu is 0.01 to 7.0% by weight, Ag is 0.01 to 2.0% by weight, and the remainder is Sn.

Cu is 0.01-7.0% by weight, Ge is 0.01-3.0% by weight, Ga is 0.01-3.0% by weight, In is 0.01-3.0% by weight, Ag is 0.01-2.0% by weight, and the rest is composed of Sn. Lead-free alloys.