CN103146975A - Lead-free low-temperature alloy having melting point of 116+/-3 DEG C and preparation method for same - Google Patents

Abstract

The invention relates to a lead-free low-temperature alloy having a melting point of 116+/-3 DEG C. The lead-free low-temperature alloy comprises the following raw materials in percentage by weight: 3.7-4.3% of bismuth, 51-53% of indium and the balance of tin. The low-temperature alloy disclosed by the invention is a lead-free low-temperature alloy containing Sn, Bi and In, can be used for producing the fusing core of a thermal fuse, and has a melting point of 116+/-3 DEG C; and the low-temperature alloy is an eutectic alloy, and has the characteristics of being uniform in ingredients, narrow in melting point range, and wide in use range.

Description

A kind of fusing point is the lead-free low-temperature Alloy And Preparation Method of 116 ± 3 ℃

Technical field

The invention belongs to the alloy field, relate to the lead-free low-temperature alloy, especially a kind of fusing core as Thermal Cutoffs, the lead-free low-temperature Alloy And Preparation Method that fusing point is 116 ± 3 ℃.

Background technology

Fusible core is the heart of Thermal Cutoffs, be the technological core of Thermal Cutoffs production technique, traditional Thermal Cutoffs mostly is tinsel, as a kind of material that is harmful to environment---lead, be detrimental to health in production and use procedure, environment is had great pollution.

Low-temperature alloy can be used for the protection of electronic circuit in electron trade, multiplex fusing core in making Thermal Cutoffs.It is that company is lived by thousand of the alpha of the U.S. and Japan that current low-temperature alloy leads the production firm of world's modern technique.

By retrieval, find following three pieces of publication documents relevant to present patent application:

1, a kind of novel environment-friendly low-temperature alloy and preparation method thereof (CN101812623A), it mainly is made of indium, tin, bismuth, zinc, silver metal.On the basis that is associated gold at Bi-In-Sn, add Zn, Ag, the metals such as Al, low-temperature alloy of the present invention can significantly be put forward heavy alloyed ductility and oxidation-resistance, has shorter melting range.

2, the lead-free low-temperature Alloy And Preparation Method (CN102296208A) that is used for the fusing core of making Thermal Cutoffs, the lead-free low-temperature alloy that relates to a kind of fusing core for making Thermal Cutoffs, its raw material consists of and weight percentage ranges is respectively: Bi:34%-36%; Zn:3.5%-4.5%; Sn: surplus; The step of its preparation method is: metallic tin is put into stainless crucible, heat on electric furnace, after the tin fusing, under 250-280 ℃, add metallic zinc, fusion clear after, then add bismuth metal, air release agent is degassed, slagging-off to carry out conventional adding after melting clearly, is cast into the low-temperature alloy rod that needs size.The lead-free low-temperature alloy that contains Sn, Bi, Zn that the present invention relates to, for the fusing core of making Thermal Cutoffs, fusing point is 132 ± 2 ℃; The characteristics such as this kind low-temperature alloy is eutectic alloy, has homogeneous chemical composition, and melting range is narrow, and cost is low, and be the leadless environment-friendly material, good social benefit and economic benefit itself had.

3, a kind of low-temperature alloy and its preparation method and application (CN102912204A) relates to a kind of lead-free low-temperature Alloy And Preparation Method and application, and this low-temperature alloy is comprised of tin, bismuth, three kinds of metals of indium, and each weight percentages of components is as follows: tin 15 ~ 17%; Bismuth 32 ~ 34%; Surplus is indium, and its preparation methods steps is: ⑴ melts tin; ⑵ melt bismuth; ⑶ melt indium; ⑷ degassed; ⑸ casting.Low-temperature alloy provided by the invention is the leadless environment-friendly material, can replace traditional tinsel, not only avoided environmental pollution and poisonous metal to the injury of human body, and guaranteed the characteristic that alloy melting point is lower, can be widely used in the production of Thermal Cutoffs, improve value-added content of product, had good social benefit.　

Compare by technology, patent application of the present invention and above-mentioned patent publication us exist more different.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art part, a kind of lead-free low-temperature Alloy And Preparation Method of the fusing core that is used for the making Thermal Cutoffs of environmental-friendly lead-free is provided, the fusing point of prepared low-temperature alloy is 116 ± 3 ℃.

The objective of the invention is to be achieved through the following technical solutions:

A kind of fusing point is the lead-free low-temperature Alloy And Preparation Method of 116 ± 3 ℃, and raw material formation and the weight percent thereof of described lead-free low-temperature alloy are as follows:

Bismuth: 3.7%-4.3%;

Indium: 51%-53%;

Tin: surplus.

And raw material formation and the weight percent thereof of described lead-free low-temperature alloy are as follows:

Bismuth: 4%;

Indium: 52%;

Tin: 44%.

Fusing point as above is the lead-free low-temperature Alloy And Preparation Method of 116 ± 3 ℃, and step is as follows:

With metallic tin heating, after fusing, under 250-280 ℃, add bismuth metal, molten clear after, then add indium metal, molten carry out degassed, slagging-off, casting after clear after, namely get the fusing core as Thermal Cutoffs, the lead-free low-temperature alloy that fusing point is 116 ± 3 ℃.

Advantage of the present invention and positively effect are:

1, low-temperature alloy of the present invention is the lead-free low-temperature alloy that contains Sn, Bi, In, can be used for making the fusing core of Thermal Cutoffs, and fusing point is 116 ± 3 ℃; This kind low-temperature alloy is eutectic alloy, has homogeneous chemical composition, and melting range is narrow, the characteristics that use range is wide.

2, low-temperature alloy of the present invention is the leadless environment-friendly material replacing traditional tinsel, and is the leadless environment-friendly material, itself has good social benefit and economic benefit.

3, preparation method's method of lead-free low-temperature alloy of the present invention is simple, and easy handling, and production cost is low, has improved the economic worth of enterprise is for the production of safety fuse has brought theoretical basis widely.

Embodiment

Further illustrate the present invention below in conjunction with specific embodiment; It is emphasized that: to those skilled in the art, can be improved according to the above description or conversion, and all these improve and conversion all should belong to the protection domain of claims of the present invention.

Metallic tin used in the present invention, indium, bismuth and air release agent are the known products of the industry.Method used in the present invention is the ordinary method of this area if no special instructions.

Embodiment 1

A kind of fusing core as Thermal Cutoffs, the lead-free low-temperature alloy that fusing point is 116 ± 3 ℃, its concrete composition is Sn ₄₄Bi ₄In ₅₂, concrete composition and weight percent are as follows:

Chemical composition %	Sn	Bi	In
				Sn 44Bi 4In 52	43.5-44.5	3.7-4.3	51-53

Fusing core, the preparation method of lead-free low-temperature alloy that fusing point is 116 ± 3 ℃ as Thermal Cutoffs as above, step is:

By weight ratio metallic tin is put into stainless crucible, after being heated to the tin fusing on electric furnace, under 250-280 ℃, add bismuth metal, fusion clear after, add again the trace elements such as indium metal and interpolation gallium, add after molten clear that air release agent is degassed, slagging-off, being cast into diameter is the low-temperature alloy rod of 25mm, vertical extruder extruding with 100 tons, extrusion temperature is 70 ℃, and mould is the 5 holes extruding of 25mm, and the low-temperature alloy silk of extruding diameter and be 1.0mm uses as the fusing core of Thermal Cutoffs.

Embodiment 2

A kind of fusing core as Thermal Cutoffs, the lead-free low-temperature Alloy And Preparation Method that fusing point is 116 ± 3 ℃, raw material formation and the weight percent thereof of described lead-free low-temperature alloy are as follows:

Bismuth: 3.7%;

Indium: 51%;

Tin: 45.3%.

The preparation method of fusing core, the lead-free low-temperature alloy that fusing point is 116 ± 3 ℃ as Thermal Cutoffs as above is with embodiment 1.

Embodiment 3

A kind of fusing core as Thermal Cutoffs, the lead-free low-temperature Alloy And Preparation Method that fusing point is 116 ± 3 ℃, raw material formation and the weight percent thereof of described lead-free low-temperature alloy are as follows:

Bismuth: 4%;

Indium: 52%;

Tin: 44%.

Embodiment 4

A kind of fusing core as Thermal Cutoffs, the lead-free low-temperature Alloy And Preparation Method that fusing point is 116 ± 3 ℃, raw material formation and the weight percent thereof of described lead-free low-temperature alloy are as follows:

Bismuth: 4.3%;

Indium: 53%;

Tin: 42.7%.

The preparation method of fusing core, the lead-free low-temperature alloy that fusing point is 116 ± 3 ℃ as Thermal Cutoffs as above is with embodiment 1.

Claims (3)

1. a fusing point is the lead-free low-temperature Alloy And Preparation Method of 116 ± 3 ℃, it is characterized in that: the raw material of described lead-free low-temperature alloy consist of and weight percent as follows:

Bismuth: 3.7%-4.3%;

Indium: 51%-53%;

Tin: surplus.

2. lead-free low-temperature alloy according to claim 1 is characterized in that: the raw material of described lead-free low-temperature alloy consist of and weight percent as follows:

Bismuth: 4%;

Indium: 52%;

Tin: 44%.

3. a fusing point as claimed in claim 1 or 2 is the lead-free low-temperature Alloy And Preparation Method of 116 ± 3 ℃, and it is characterized in that: step is as follows:

With metallic tin heating, after fusing, under 250-280 ℃, add bismuth metal, molten clear after, then add indium metal, molten carry out degassed, slagging-off, casting after clear after, namely get the fusing core as Thermal Cutoffs, the lead-free low-temperature alloy that fusing point is 116 ± 3 ℃.