CN104032164A

CN104032164A - Leadless free-cutting silicon brass alloy material and preparation method thereof

Info

Publication number: CN104032164A
Application number: CN201410197393.XA
Authority: CN
Inventors: 陈大军
Original assignee: BENGBU HONGWEI FILTER Co Ltd
Current assignee: BENGBU HONGWEI FILTER Co Ltd
Priority date: 2014-05-12
Filing date: 2014-05-12
Publication date: 2014-09-10

Abstract

A leadless free-cutting silicon brass alloy material comprises the chemical elements in percent by mass: 16-19% of Zn, 1.6-1.9% of Si, 2.1-2.3% of Be, 0.03-0.05% of La, 0.16-0.19% of Ho, and the balance Cu. By adding Si, La and Ho into brass alloy, the copper alloy is improved in cutting performance, wear resistance and electric conductivity, and is leadless and nontoxic; by adding Be, the copper is improved in elasticity, corrosion resistance and fatigue resistance; and by reasonably controlling the processing temperature after casting and taking waste copper as a raw material, the hardness of the core part and the hardness of the surface are basically consistent, and the alloy quality is uniform. An employed refining agent is used for casting production, is capable of reducing the porosity degree of a casting by 1-2 degree and enabling the oxide inclusions to be around second grade, and helps to obviously improve the yield.

Description

A kind of leadless free-cutting silicon brass alloy material and preparation method thereof

Technical field

The manufacture field that the present invention relates to metal alloy compositions, relates in particular to a kind of leadless free-cutting silicon brass alloy material and preparation method thereof.

Background technology

Copper is because of its good electroconductibility, plasticity-, and erosion resistance, applies very extensive.In copper alloy, add Lv ﹑ Nie ﹑ Meng ﹑ Xi ﹑ Gui ﹑ lead and other elements, can improve the performance of copper, for different places.Still there are some problems in the existing copper alloy of China at present, and as alloy contains a large amount of impurity elements, high temperature fatigue is poor, hot strength is low; Hardness is low, wears no resistance, frictional coefficient is large, and work-ing life is short; Poorly conductive, waste electric energy; Bending machining performance is poor, easily fractures; Quality weight, constructional difficulties; Can't meet market demands.

Summary of the invention

The object of the present invention is to provide a kind of leadless free-cutting silicon brass alloy material and preparation method thereof, this Cu alloy material has advantages of easy cutting, corrosion-resistant, asepsis environment-protecting.

Technical scheme of the present invention is as follows:

A kind of leadless free-cutting silicon brass alloy material, is characterized in that: chemical element composition and mass percent thereof that it contains are: zinc 16-19, silicon 1.6-1.9, Be2.1-2.3, La0.03-0.05, Ho0.16-0.19, surplus are copper.

The production method of described leadless free-cutting silicon brass alloy material, is characterized in that:

(1), preparing fine copper and copper scrap originates as copper matrix in 1:0.4-0.7 ratio, fine copper is added to drop in stove and melt, carry out removing impurities matter, deoxidation, employing refining agent initial refining, add alloying constituent and carry out alloying, then add copper scrap fusing, add refining agent secondary refining, detection and adjust chemical element component content to qualified, casting, casting postheat treatment etc.;

(2) in alloying process, to the lot sequence that drops into alloying element in stove be: (1) zinc; (2) silicon, La; (3) other remaining components; The each batch of timed interval of dropping into element is 22-25 minute, after feeding intake, stirs.

Described casting postheat treatment is: be first warming up to 250-260 DEG C by room temperature with 220-230 DEG C/h of speed, and insulation 50-60 minute, then be warming up to 560-570 DEG C with 240-250 DEG C/h of speed, insulation 1-2 hour; Be cooled to 80-100 DEG C with 270-280 DEG C/h of speed again, insulation 1-2 hour; Be warming up to 350-360 DEG C with 210-220 DEG C/h of speed again, insulation 1-2 hour; Be cooled to 80-100 DEG C with 250-260 DEG C/h of speed again, insulation 1-2 hour; Be warming up to 310-330 DEG C with 180-190 DEG C/h of speed again, insulation 2-3 hour, takes out air cooling and get final product.

Described refining agent is made up of the raw material of following weight part: silicon-dioxide 8-12, attapulgite 8-12, vermiculite 5-8, attapulgite 8-10, medical stone 3-4, trees ashes 1-2, Repone K 5-8, Calcium Fluoride (Fluorspan) 3-5, SODIUMNITRATE 3-5; Its preparation method is that silicon-dioxide, attapulgite, vermiculite, attapulgite, medical stone, trees ashes are mixed, be heated to 2600-3000 DEG C, stir 1-2 hour, after cooling, be added in the hydrochloric acid soln of 10-15%, soak 1-2 hour, filter, filter residue is cleaned with clear water repeatedly, dries, and merges and mixes and get final product with other composition.

Beneficial effect of the present invention

Brass alloys of the present invention, by adding silicon, La, Ho, have improved cutting ability, wear resistance and the conductivity of copper alloy, and unleaded nontoxic; By adding Be, elasticity, erosion resistance and resistance to fatigue are increased; By reasonable control casting post-processing temperature, use copper scrap as raw material, make core hardness and surface hardness basically identical, alloy quality homogeneous.Refining agent of the present invention, for Foundry Production, can make the degree of porosity in foundry goods reduce 1-2 degree, and oxide inclusion, 2 grades of left and right, obviously improves yield rate.

Embodiment

A kind of leadless free-cutting silicon brass alloy material, chemical element composition and mass percent thereof that it contains are: zinc 16-19, silicon 1.6-1.9, Be2.1-2.3, La0.03-0.05, Ho0.16-0.19, surplus are copper.

The production method of described leadless free-cutting silicon brass alloy material is as follows:

(1), preparing fine copper and copper scrap originates as copper matrix in 1:0.6 ratio, fine copper is added to drop in stove and melt, carry out removing impurities matter, deoxidation, employing refining agent initial refining, add alloying constituent and carry out alloying, then add copper scrap fusing, add refining agent secondary refining, detection and adjust chemical element component content to qualified, casting, casting postheat treatment etc.;

(2) in alloying process, to the lot sequence that drops into alloying element in stove be: (1) zinc; (2) silicon, La; (3) other remaining components; The each batch of timed interval of dropping into element is 23 minutes, after feeding intake, stirs.

Described casting postheat treatment is: be first warming up to 255 DEG C by room temperature with 225 DEG C/h of speed, be incubated 55 minutes, then be warming up to 565 DEG C with 245 DEG C/h of speed, be incubated 1.5 hours; Be cooled to 90 DEG C with 275 DEG C/h of speed again, be incubated 1.5 hours; Be warming up to 355 DEG C with 215 DEG C/h of speed again, be incubated 1.5 hours; Be cooled to 90 DEG C with 255 DEG C/h of speed again, be incubated 1.5 hours; Be warming up to 320 DEG C with 185 DEG C/h of speed again, be incubated 2.5 hours, take out air cooling and get final product.

Described refining agent by following weight part (kilogram) raw material make: silicon-dioxide 8, attapulgite 8, vermiculite 8, attapulgite 8, medical stone 3, trees ashes 1, Repone K 8, Calcium Fluoride (Fluorspan) 5, SODIUMNITRATE 5; Its preparation method is that silicon-dioxide, attapulgite, vermiculite, attapulgite, medical stone, trees ashes are mixed, be heated to 2600-3000 DEG C, stir 1-2 hour, after cooling, be added in the hydrochloric acid soln of 10-15%, soak 1-2 hour, filter, filter residue is cleaned with clear water repeatedly, dries, and merges and mixes and get final product with other composition.

The present embodiment leadless free-cutting silicon brass alloy material, tensile strength б b is 579Mpa, yield strength 523MPa, hardness value HB is 143, electric conductivity %IACS70,598 DEG C of softening temperatures, 20 DEG C of unit elongation 15.3%.

Claims

1. a leadless free-cutting silicon brass alloy material, is characterized in that: chemical element composition and mass percent thereof that it contains are: zinc 16-19, silicon 1.6-1.9, Be2.1-2.3, La0.03-0.05, Ho0.16-0.19, surplus are copper.

2. the production method of leadless free-cutting silicon brass alloy material according to claim 1, is characterized in that:

3. the production method of leadless free-cutting silicon brass alloy material according to claim 2, it is characterized in that: described casting postheat treatment is: be first warming up to 250-260 DEG C by room temperature with 220-230 DEG C/h of speed, insulation 50-60 minute, be warming up to 560-570 DEG C with 240-250 DEG C/h of speed again, insulation 1-2 hour; Be cooled to 80-100 DEG C with 270-280 DEG C/h of speed again, insulation 1-2 hour; Be warming up to 350-360 DEG C with 210-220 DEG C/h of speed again, insulation 1-2 hour; Be cooled to 80-100 DEG C with 250-260 DEG C/h of speed again, insulation 1-2 hour; Be warming up to 310-330 DEG C with 180-190 DEG C/h of speed again, insulation 2-3 hour, takes out air cooling and get final product.

4. the production method of leadless free-cutting silicon brass alloy material according to claim 2, is characterized in that: described refining agent is made up of the raw material of following weight part: silicon-dioxide 8-12, attapulgite 8-12, vermiculite 5-8, attapulgite 8-10, medical stone 3-4, trees ashes 1-2, Repone K 5-8, Calcium Fluoride (Fluorspan) 3-5, SODIUMNITRATE 3-5; Its preparation method is that silicon-dioxide, attapulgite, vermiculite, attapulgite, medical stone, trees ashes are mixed, be heated to 2600-3000 DEG C, stir 1-2 hour, after cooling, be added in the hydrochloric acid soln of 10-15%, soak 1-2 hour, filter, filter residue is cleaned with clear water repeatedly, dries, and merges and mixes and get final product with other composition.