CN1038520C

CN1038520C - Anti-softnening high pure silver material

Info

Publication number: CN1038520C
Application number: CN 93108789
Authority: CN
Inventors: 宁远涛; 赵怀志; 邓德国; 文飞
Original assignee: KUNMING NOBLE METAL INST CHINA NONFERROUS METAL INDUSTRY GENERAL Co
Current assignee: KUNMING NOBLE METAL INST CHINA NONFERROUS METAL INDUSTRY GENERAL Co
Priority date: 1993-07-19
Filing date: 1993-07-19
Publication date: 1998-05-27
Anticipated expiration: 2013-07-19
Also published as: CN1095113A

Abstract

The present invention relates to a high-purity silver material containing rare-earth elements. The rare-earth elements contained in the silver material are at least one of RE with the content of 10 to 100 ppm (RE is Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu). The silver material has a higher self-softening resistance, and the electrical property of the silver material is equal to that of the existing high-purity silver materials. The silver material can substitute for the existing high-purity silver materials to be used as an electrode material, an outer shell material of a capacitor, an electric contact material, and a conductor material for instruments and meters.

Description

Contain the anti-of rare earth element from softening silver alloys

The present invention relates to contain the anti-of rare earth element from the remollescent silver alloys.

High-purity silver material has good conductive, heat conductivility, be excellent electrical conductor and heat conductor, widespread use in industry, for example the Ag1 of present industrial use (purity 99.99%) is mainly used to make good conduction, heat conductor, the materials such as battery electrode that tantalum capacitor shell and space flight and aviation are used; Ag2 (purity 99.9%) is mainly used to make fine silver contact and conductor material.It is low that but one of disadvantage of fine silver is an intensity, and recrystallization temperature is low, just has the nature reply phenomenon in room temperature.Though cold deformation can make the intensity of fine silver improve, but between storage and usage period, the natural reply phenomenon of silver can make its hardness and intensity descend rapidly, unit elongation increases, and the deformation subgrain is grown up etc., that is to say, the mechanics of the high-purity silver material of cold deformation attitude, electric property and microstructure all are in a kind of unsteady state, and it is softening also from ruckbildung promptly to exist nature to reply, and this uses silver-colored material and causes detrimentally affect.

It is replied for the purity of silver material and cold deformation amount and recrystallize has tangible influence, the purity of silver material is high more and cold deformation that bear is big more, its recrystallization temperature is low more, otherwise, the cold deformation amount that reduces the purity of silver-colored material and born can improve recrystallization temperature, the anti-answer that correspondingly can improve silver-colored material is softening anti-in other words from softening power, therefore, Xiang Yinzhong adds alloying element, especially a small amount of simple metal or the transition metal that have certain solid solubility, can improve recrystallization temperature, for example in No. 1 silver and No. 2 silver-colored materials, add a small amount of Cu, Ni, Ti etc. can suppress the softening certainly of silver-colored material to a certain extent.

But, when adding some transition metal, because its atomic radius differs very little with the atomic radius of silver, solid solution strengthening effect is very little, must add the effect that high level just can reach solution strengthening and improve recrystallization temperature to, and too high other performances that can influence silver-colored material of foreign matter content especially make resistivity obviously raise.

The objective of the invention is to overcome the shortcoming of existing high-purity silver material material, propose a kind of recrystallization temperature height, have anti-ly from softening power, the silver alloys that contains rare earth that its electrical property and existing high-purity silver material are suitable substantially is to replace existing high-purity silver material.

Technical scheme of the present invention is to introduce trace rare-earth one or more comprising from Y, La, Ce to whole elements of Yb, Lu to make silver-colored solution strengthening in the high fine silver of purity more than 99.9%.

The composition of silver alloys of the present invention is: rare earth elements RE=0.001-0.01 weight %, surplus are silver.RE is at least a among Y, La, Ce, Pr, Nd, Pm, Sm, En, Gd, Tb, Dy, Ho, Er, Tm, Yb, the Lu.

Rare earth element has certain solid solubility in silver, therefore their atomic radius, is solid-solubilized in the silver matrix with trace rare-earth element than the atomic radius big (seeing Table 1) of silver, can significantly improve recrystallization temperature, have solution strengthening and suppress to reply the remollescent ability.By table 1 as seen, Eu and Yb are the maximum and inferior big elements of atomic radius in the rare earth element, and therefore, their strengthening effect is the strongest.In addition, the atomic radius of light rare earths is bigger than heavy rare earth element, and its solid solubility is less than heavy rare earth element in silver, therefore, the strengthening effect of light rare earths is greater than the strengthening effect of heavy rare earths.

The content of the rare earth element that silver alloys of the present invention is introduced is controlled in the 0.001-0.01 weight % concentration range, rare earth concentration is lower than 0.001 weight %, do not reach reinforcement and anti-from the remollescent purpose, and concentration is higher than 0.01 weight %, make total impurities content rising in the silver on the one hand, cause on the other hand other performance particularly electric property to increase amplitude excessive, and produce detrimentally affect.For rare earth Eu and Yb with maximum radius and time thick atom radius, their concentration the best can be controlled in the 0.001-0.003 weight %, and for light rare earths RE1 (Y, La, Ce, Pr, Na, Pm, Sm, Eu) concentration the best can reach 0.002-0.005 weight %, heavy rare earth element RE2 (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) the concentration optimum control is in 0.005-0.01 weight % scope, the rare earth element of introducing, it can be single-element, can be two or more mixing also, the weight rare earth complex element that is controlled in the above-mentioned concentration range also has good effect.

The silver alloys that contains trace rare-earth element of the present invention, can replace Ag1 and Ag2 as electrode materials, capacitor case material, contact material and instrument with conductor material etc.

Embodiment: adopting purity is that 99.999% rare earth is as the preparation of raw material binary alloy.With high-quality crucible pollution-free melting ingot casting in totally-enclosed system, the control content of rare earth.Ingot casting is become a useful person through cold deformation, its salient features of gained silver alloys is listed in table 2, this shows, compares with the pure Ag material that does not contain rare earth, the Ag resistance alloys rate rising amplitude that contains rare earth is very little, but intensive property obviously raises, after depositing 1 year, and pure Ag material lowered hardness 43%, unit elongation increases 23 times, obviously oneself is softening, and contains the alloy rigidity value and the basic no change of unit elongation of trace rare-earth, has tangible anti-softening power.

The atomic radius of table 1 rare earth element and the solid solubility in Ag

Element	Y	La	Ce	Pr	Nd	Pm	Eu	Gd
Element	Y	La	Ce	Pr	Nd	Pm	Eu	Gd	Atomic radius	1.801	1.877	1.824	1.828	1.821	1.810	2.042	1.802
Solid solubility in Ag (% by weight)	1.31	0.05	0.05	0.065	0.25	—	0.02	1.40	Atomic radius	1.801	1.877	1.824	1.828	1.821	1.810	2.042	1.802
Solid solubility in Ag (% by weight)	1.31	0.05	0.05	0.065	0.25	—	0.02	1.40	Element	Dy	Ho	Er	Tm	Yb	Lu	Ag
Atomic radius	1.773	1.766	1.757	1.940	1.940	1.734	1.442		Element	Dy	Ho	Er	Tm	Yb	Lu	Ag
Atomic radius	1.773	1.766	1.757	1.940	1.940	1.734	1.442		Solid solubility in Ag (% by weight)	1.95	2.40	5.50	6.98	3.04	—	—

The Performance Ratio of table 2, fine silver and silver alloy of the present invention

Embodiment	Add element	Add content (% by weight)	Intensity Mpa	Hardness	Percentage elongation %	Recrystallization temperature	Resistivity	Deposit performance variation after 18 months
								Deposit performance variation after 18 months				Hardness	Rate of change	Percentage elongation %	Rate of change
								Fine silver	—	—	345	Hardness	Rate of change	Percentage elongation %	Rate of change	85	1.5	70	1.71	54	43	35	23 times
RAg1	Ce	0.003	420	95	2	110	1.74	Fine silver	—	—	345	94	1	2	Do not become	85	1.5	70	1.71	54	43	35	23 times
RAg1	Ce	0.003	420	95	2	110	1.74	RAg2	Eu	0.0016	400	94	1	2	Do not become	90	1.5	90	1.74	88	2	1.5	Do not become
RAg3	Gd	0.008	380	90	2	88	1.75	RAg2	Eu	0.0016	400	89	1	2	Do not become	90	1.5	90	1.74	88	2	1.5	Do not become
RAg3	Gd	0.008	380	90	2	88	1.75	RAg4	Er	0.0085	390	89	1	2	Do not become	95	2	86	1.75	90	5	2	Do not become
RAg5	Ce Gd	0.001 0.003	380	90	2	88	1.74	RAg4	Er	0.0085	390	90	2	2	Do not become	95	2	86	1.75	90	5	2	Do not become
RAg5	Ce Gd	0.001 0.003	380	90	2	88	1.74	RAg6	Y Nd Tm	0.0015 0.0025 0.003	400	90	2	2	Do not become	90	2	90	1.75	90		2	Do not become
RAg7	La Ce Gd Er	0.001 0.002 0.002 0.003	400	95	1.5	90	1.75	RAg6	Y Nd Tm	0.0015 0.0025 0.003	400	92	5	1.5	Do not become	90	2	90	1.75	90		2	Do not become

Claims

1, a kind of silver alloys that contains trace rare-earth element, it is characterized in that contained rare earth element is at least a among the RE (Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), content is 0.001-0.01 weight %, and surplus is a silver.

2, according to the described silver alloys of claim 1, it is characterized in that contained rare earth element is at least a among the RE (La, Ce, Pr, Nd, Pm, Sm), content is 0.002-0.005 weight %, surplus is a silver.

3, according to claim 1 or 2 described silver alloys, it is characterized in that contained rare earth element is Ce, content is 0.002-0.003 weight %, surplus is a silver.

4, according to the described silver alloys of claim 1, it is characterized in that contained rare earth elements RE is a kind of among Eu, the Yb, content is 0.001-0.003 weight %, surplus is a silver.

5, according to the described silver alloys of claim 1, it is characterized in that contained rare earth element is at least a among the RE (Gd, Tb, Dy, Ho, Er, Tm, Lu), its total content is 0.005-0.01 weight %, surplus is a silver.

6, according to claim 1 or 5 described silver alloys, it is characterized in that contained rare earth element is Gd, content is 0.005-0.008 weight %, surplus is a silver.