CN102255211B

CN102255211B - Palladium silver electrical contact material with high wear resistance

Info

Publication number: CN102255211B
Application number: CN 201110092385
Authority: CN
Inventors: 徐永红; 匡纲要; 章应; 秦秀芳; 陈容
Original assignee: SHENZHEN WEIZHEN MOTOR CO Ltd; Chongqing Chuanyi Automation Co Ltd
Current assignee: SHENZHEN WEIZHEN MOTOR CO Ltd; Chongqing Chuanyi Automation Co Ltd
Priority date: 2011-04-13
Filing date: 2011-04-13
Publication date: 2013-07-24
Anticipated expiration: 2031-04-13
Also published as: CN102255211A

Abstract

The invention relates to a palladium silver electrical contact material with high wear resistance. The palladium silver electrical contact material consists of the following components in percentage by weight: 40 to 48 percent of Pd, 1 to 10 percent of Cu, 0.05 to 1 percent of RE and the balance of Ag, or consists of the following components in percentage by weight: 40 to 48 percent of Pd, 1 to 10 percent of Cu, 0.05 to 1 percent of RE, 0.05 to 0.5 percent of AM and the balance of Ag, wherein in the material, RE is one or more of La, Ce, Nd, Sm, Eu, Gd and Er and AM is one or more of Li, Na and K. The cost of the material is lower than that of AgPd50 alloy and the material has excellent wear resistance and electrical contact performance; and an alloy compounded by the material and copper or copper alloy is applicable to manufacturing of a brush for a small direct-current motor.

Description

Palladium-silver with high-wearing feature is a contact material

Technical field

The present invention relates to metal material always, be particularly related to a kind of Cu of interpolation, rare earth and palladium-silver alkali-metal, that have high-wearing feature and be slip alloy as electric contact material and this alloy and make working lining, copper or copper alloy and make the laminar composite that basic unit forms, and use brush sheet that laminar composite makes and the DC motor of using this brush sheet.

Background technology

The brush sheet is one of core parts of DC motor, and it and commutator constitute slip and electrically contact the even part of conduction.Bear the double action of skimming wear and arc erosion in the course of the work, also be subjected to the influence of various Korrosionsmediums in the ambiance simultaneously.Therefore, the brush sheet material also needs good resistance to wear, arc resistant ability and corrosion resistance when requiring satisfactory electrical conductivity; Simultaneously, brush sheet and commutator pairing work, the rational Match of its two performance has decisive influence to the performance and the life-span of DC motor.For a long time, in AgPd30 and AgPd50 (i.e. percentage by weight, the Pd content of alloy is respectively 30% and 50%) alloy makes the brush sheet of the material of working lining, with AgCuNi be alloy (comprising AgCuNi, AgCuZnNi, AgCuPdZnNi etc.) for the commutator pairing of working lining obtains to use widely in DC motor, and obtain good effect.

In order to improve the performance of DC motor, Chinese invention patent 200810069483.5,200810070322.8 and 200910303095.3 has been developed the silver-based electric contact material that contains rare earth, and is the commutator that working lining is used to make DC motor with it; This class commutator and traditional AgPd50 brush sheet pairing use, stability, reliability and the useful life of obviously having improved DC motor.A large amount of result of practical application show, under this pairing condition, the resistance to wear of AgPd50 brush sheet working lining shows tangible deficiency, under a lot of situations, also have more than 50% under the remaining situation at commutator working lining thickness, the just whole wearing and tearing of the working lining of brush sheet exhaust, and in the time of serious, also cause the DC motor performance significantly to descend even inefficacy because of brush sheet working lining premature wear exhausts.Therefore, improve the resistance to wear of brushing sheet and become the important technical of giving full play to noble metal contact material premium properties and further improving stability, reliability and the useful life of DC motor.

Yet, the Pd amount that contains of AgPd alloy is brought up to 60-70% (percetage by weight), can improve its hardness, thereby improve the resistance to wear of brush sheet, but this can increase material cost greatly, be difficult to obtain the market approval; Also have to use and contain the report that the Cu amount is the PdAgCu alloy making brush sheet of 30% (percetage by weight), but measure too high because it contains Cu, alloy corrosion resistance obviously descends, the scope of application is very limited, and is not suitable for using under the condition of high temperature, high humidity and the medium that is corrosive (as contain S environment); And contact resistance changes greatly in the use, causes the reduction of DC motor stability, electrical noise increase, output waveform to worsen.

Summary of the invention

At existing palladium-silver is the problem that the brush sheet material exists, the invention provides a kind of palladium-silver with high-wearing feature is contact material, described material is by multi-element alloyed, have high-wearing feature,, use with the money base commutator pairing that contains rare earth with its working face as the brush sheet, optimize the matching performance of the two, give full play of the premium properties of noble metal contact material, under the prerequisite that guarantees DC motor stability, further improve its useful life.

Technical scheme of the present invention is:

A kind of palladium-silver is an alloy as electric contact material, is made up of Pd, Cu, RE, Ag, and each composition percentage composition by weight is:

Pd 40-48％；

Cu 1-10％；

RE 0.05-1％；

Surplus is Ag;

Wherein, RE is one or more in La, Ce, Nd, Sm, Eu, Gd, the Er element.

A kind of palladium-silver is an alloy as electric contact material, is made up of Pd, Cu, RE, AM, Ag, and each composition percentage composition by weight is:

Pd 40-48％；

Cu 1-10％；

RE 0.05-1％；

AM 0.05-0.5％；

Surplus is Ag;

Wherein, RE is one or more in La, Ce, Nd, Sm, Eu, Gd, the Er element; AM is one or more in Li, Na, the K element.

Being used for the two-layer laminar composite that slidingtype electrically contacts, is alloy as electric contact material and copper or the compound composite material that obtains of copper alloy by above-mentioned palladium-silver, wherein palladium-silver be alloy as electric contact material as working lining, copper or copper alloy are as basic unit.

Described Alba alloy layer segment or all be compounded in copper or copper alloy basic unit on.

Brush plate with above-mentioned laminar composite preparation.

Use above-mentioned brush sheet in the DC motor.

Palladium-silver of the present invention is in the alloy as electric contact material, since copper and silver all infinitely solid solution in palladium, performance solution strengthening effect, and the difference of copper (0.128nm) and palladium (0.137nm) atomic radius silver (0.144nm) is big with the difference of palladium atomic radius, so copper to the solution strengthening effect of palladium greater than silver, and produce reciprocation between the multiple alloying element, can give play to than two kinds of better invigoration effects of element, therefore, the present invention's copper of adding 1-10% can improve the hardness and the resistance to wear of palladium-silver.Its reason be Cu at room temperature almost completely can not solid solution in Ag, if Cu adds too much (greater than 10%), larger-size precipitated phase then appears easily, increase itself and the contact resistance of commutator material, the waveform of deterioration DC motor; If instead Cu adds very few (being less than 1%), then can not bring into play its invigoration effect.

The rare earth element of 0.05-1% in the material of the present invention has the impurity of removal, purifies alloy, improves homogeneity of ingredients, the thinning microstructure of alloy, thereby improves the conductivity and the mechanical property of alloy; Simultaneously, rare earth element can also form multiple intermetallic compound with Ag, Pd, Cu, and with the disperse from matrix of subparticle form, separate out equably, produce the precipitation strength effect, improve the resistance to wear of alloy, and improve its high-temperature stability, suppress the brush sheet and owing to temperature raises softening phenomenon takes place in the course of the work, thereby prolong the useful life of brush sheet.Ree content is that the reason of 0.05-1% is, if rare earth adds too much (greater than 1%), then precipitated phase increases, size becomes big, and contact resistance raises, and the damage of commutator is increased, and is unfavorable for the improvement in DC motor performance and life-span; Otherwise,, then can not bring into play its beneficial effect if the rare earth addition (is less than 0.05%) very little.

Micro-alkali metal lithium, sodium, the potassium of 0.05-0.5% in the material of the present invention, but solid solution is in matrix, its character is active, very easily oxidation in air, in the contact material course of work, alkali metal preferential oxidation in the alloy, form the oxidation film that peels off easily at material surface, thereby generation self-lubricating function, particularly reduce commutator and direct contact of brushing the sheet metal surface, reduce the material damage that adhesive wear causes to a great extent, and this oxidation film is very thin, can not increase contact resistance.Simultaneously, alkali-metal boiling point is lower, volatilizees easily when being subjected to high temperature action, thereby can take away the heat of electric arc, and electric arc is extinguished as early as possible, greatly reduces the ablation of contact material.Alkali-metal content is that the reason of 0.05-0.5% is, if alkali metal adds too much (greater than 0.5%), then resistance alloys increases too much, and the brush sheet of making temperature rise in the course of the work increases, the softening easily damage of material, and the current efficiency of reduction DC motor; Otherwise,, then can not effectively bring into play its lubricated and arc extinguishing effect if the alkali metal addition (is less than 0.05%) very little.

Advantage of the present invention is:

1) adopt Ag-Pd-Cu-RE of the present invention or Ag-Pd-Cu-RE-AM contact material to make electrical micro-machine brush sheet, have better wear resistance and high-temperature stability, use stability and the useful life that to improve DC motor with the money base commutator pairing that contains rare earth.

2) Ag-Pd-Cu-RE of the present invention or Ag-Pd-Cu-RE-AM alloy as electric contact material can adopt the manufacturing of conventional vacuum smelting technology, and equipment and technology do not need special transformation, and be easy to implement in the production.

When 3) utilizing Ag-Pd-Cu-RE of the present invention or Ag-Pd-Cu-RE-AM alloy as electric contact material to make laminar composite, the technology and the equipment that can adopt existing palladium-silver/copper alloy to electrically contact composite strip are produced, technology is easy to grasp and implement, and also can not increase production cost.

4) alloy of the present invention passes through the multi-element alloyed of Cu, rare earth element and alkali metal, with existing AgPd50 alloy phase ratio, under the prerequisite of guaranteed performance, has reduced the content of expensive Pd, can reduce material cost.

The alloy that material of the present invention and copper or copper alloy are compound is suitable for making the brush sheet of small-sized DC motor.

Embodiment

The cogging that the present invention adopts, rolling, intermediate annealing, drawing, hot rolling, warm-rolling or cold rolling combination process adopt the technology of the production commonly used in material preparation and the manufacture field.

Prepare the method that palladium-silver of the present invention is a contact material:

1) adopt vacuum induction melting to prepare alloy, wherein Cu, La, Ce, Nd, Sm, Eu, Gd, Er, Li, Na, K element can add with the intermediate alloy form, also can add with form of pure metal; If rare earth element and alkali metal add with form of pure metal, then rare earth element and alkali metal must be placed in the glove box of nitrogen protection with taking out behind silver foil or the silver strip environmental sealing, add again, to prevent its oxidation, in order to avoid its oxidizing fire in air; In addition, can also utilize in the production process raw material of leftover pieces discarded, that composition is qualified as the preparation new alloy.

2) with the Ag-Pd-Cu-RE of preparation or Ag-Pd-Cu-RE-AM alloy as electric contact material ingot casting through technologies such as cogging, rolling, intermediate annealing, drawings, be prepared into band or silk material.

3) adopt hot rolling, warm-rolling or cold rolling complex technique, above-mentioned band or silk material and copper alloy are carried out compound, be made into laminar composite.Palladium-silver wherein of the present invention is that contact material is a working lining, and copper or copper alloy are basic unit.

The alloying component of embodiment 1 to 49 sees Table 1.

Table 1 embodiment 1-49 alloying component (percetage by weight)

Embodiment	Pd	Cu	La	Ce	Nd	Sm	Eu	Gd	Er	Ag
											1	40	10	0.05					Surplus
2	40	10		0.05						Surplus
											3	40	10			0.05			Surplus
4	40	10				0.05				Surplus
											5	40	10				0.05		Surplus
6	40	10						0.05		Surplus
											7	40	10					0.05	Surplus
8	42	8	0.2							Surplus
											9	42	8		0.2				Surplus

10	42	8			0.2					Surplus
											11	42	8				0.2				Surplus
12	42	8					0.2			Surplus
											13	42	8						0.2		Surplus
14	42	8							0.2	Surplus
											15	45	5	0.4							Surplus
16	45	5		0.4						Surplus
											17	45	5			0.4					Surplus
18	45	5				0.4				Surplus
											19	45	5					0.4			Surplus
20	45	5						0.4		Surplus
											21	45	5							0.4	Surplus
22	48	1	1							Surplus
											23	48	1		1						Surplus
24	48	1			1					Surplus
											25	48	1				1				Surplus
26	48	1					1			Surplus
											27	48	1						1		Surplus
28	48	1							1	Surplus
											29	40	10	0.05		0.05		0.02			Surplus
30	40	10		0.05		0.03		0.03		Surplus
											31	40	10		0.05	0.05		0.02			Surplus
32	40	10		0.03		0.05		0.02	0.02	Surplus
											33	40	10	0.02		0.03		0.05		0.02	Surplus
34	40	10	0.02			0.02		0.05		Surplus
											35	40	10		0.03			0.03		0.05	Surplus
36	45	5	0.1		0.05					Surplus
											37	45	5		0.2		0.03		0.03		Surplus
38	45	5		0.02	0.2		0.02			Surplus
											39	45	5		0.03		0.2		0.02	0.02	Surplus
40	45	5	0.02		0.03		0.2		0.02	Surplus
											41	45	5	0.02			0.02		0.2		Surplus
42	45	5		0.02			0.02		0.2	Surplus
											43	48	1	0.5		0.5					Surplus
44	48	1		0.5		0.3		0.2		Surplus
											45	48	1		0.3	0.5		0.2			Surplus
46	48	1		0.2		0.4		0.2	0.2	Surplus
											47	48	1	0.2		0.1		0.5		0.2	Surplus
48	48	1	0.2			0.2		0.6		Surplus
											49	48	1		0.2			0.3		0.5	Surplus

Prepare the method that palladium-silver is a contact material by each composition of getting in the table 1 according to above-mentioned, the preparation palladium-silver is electrical contact alloy material and is cast into ingot, make band through operations such as cogging, rolling, annealing, adopt the compound laminar composite that obtains of hot rolling combination process and BZn18-26 copper alloy then, continue then through repeatedly being rolled into Pd-Ag-Cu-RE alloy bed thickness 0.01mm, the composite strip of total thickness 0.15mm.

Comparative example 1 alloying component is: 50%Pd, surplus are Ag, adopt with the various embodiments described above same process and make Pd-Ag alloy bed thickness 0.013mm, the composite strip of total thickness 0.15mm.

Band is used to be made into DC motor brush sheet, should brushes sheet and be assemblied in the DC motor, carry out life test.Corresponding commutator material is AgCu4Ni0.5RE/Cu, and wherein, ag alloy layer thickness is 0.03mm, material gross thickness 0.25mm.

Test condition is:

Probe temperature: 70 ℃; Testing load: φ 12mm CD; Test voltage: 3V; Rotating speed: 5000RPM; Operational mode: continuously; Every group of testing of electric motors quantity: 10.

In the test process, judge the operating state of motor, rotating speed or electric current occur and exceed standard and all be judged to be end-of-life in the time of maybe can't starting that the life value of each group test motor is all got its 10 motor mean value calculation by the variation that detects motor speed and electric current.

Test result sees Table 2.

Table 2 embodiment 1-49 and comparative example 1 life test result

Embodiment	Life-span
		1	5320
2	5210
		3	5220
4	5190
		5	5230
6	5050
		7	5120
8	5120
		9	5210
10	5330
		11	5250
12	5270

13	5310
		14	5320
15	5420
		16	5410
17	5390
		18	5420
19	5290
		20	5460
21	5330
		22	5340
23	5420
		24	5410
25	5280
		26	5380
27	5410
		28	5250
29	5360
		30	5330
31	5380
		32	5360
33	5290
		34	5430
35	5320
		36	5410
37	5380
		38	5360
39	5420
		40	5330
41	5320
		42	5290
43	5310
		44	5280
45	5290
		46	5320
47	5290
		48	5410

49	5360
		Comparative example 1	4120

The alloying component of embodiment 50 to 73 sees Table 1.

Table 3 embodiment 50-73 alloying component (percetage by weight)

Embodiment	Pd	Cu	RE	Li	Na	K	Ag
								50	40	10	0.05	0.05			Surplus
51	40	10	0.05		0.05		Surplus
								52	40	10	0.05			0.05	Surplus
53	42	8	0.1	0.1			Surplus
								54	42	8	0.1		0.1		Surplus
55	42	8	0.1			0.1	Surplus
								56	45	5	0.4	0.3			Surplus
57	45	5	0.4		0.3		Surplus
								58	45	5	0.4			0.3	Surplus
59	48	2	1	0.5			Surplus
								60	48	2	1		0.5		Surplus
61	48	2	1			0.5	Surplus
								62	40	10	0.05	0.02	0.03		Surplus
63	40	10	0.05		0.02	0.03	Surplus
								64	40	10	0.05	0.03		0.02	Surplus
65	40	10	0.05	0.02	0.02	0.01	Surplus
								66	45	5	0.3	0.05	0.05		Surplus
67	45	5	0.3		0.05	0.05	Surplus
								68	45	5	0.3	0.05		0.05	Surplus
69	45	5	0.3	0.03	0.03	0.04	Surplus
								70	48	2	1	0.2	0.3		Surplus
71	48	2	1	0.3		0.2	Surplus
								72	48	2	1		0.2	0.3	Surplus
73	48	2	1	0.2	0.1	0.2	Surplus

Get each composition by table 3 and prepare the method that palladium-silver is a contact material according to above-mentioned, the preparation palladium-silver is electrical contact alloy material and is cast into ingot, make band through operations such as cogging, rolling, annealing, adopt the compound laminar composite that obtains of hot rolling combination process and BZn18-26 copper alloy then, continue then through repeatedly being rolled into Pd-Ag-Cu-RE alloy bed thickness 0.01mm, the composite strip of total thickness 0.15mm.

Comparative example 2 alloying components are: 50%Pd, surplus are Ag, adopt with the various embodiments described above same process and make Pd-Ag alloy bed thickness 0.013mm, the composite strip of total thickness 0.15mm.

Test condition is:

Probe temperature: 70 ℃; Testing load: 12gcm; Test voltage: 3V; Rotating speed: 7000RPM; Operational mode: continuously; Every group of testing of electric motors quantity: 10.

Table 4 embodiment 50-73 and comparative example 2 life test results

Embodiment	Life-span
		50	4880
51	4850
		52	4930
53	4870
		54	4860
55	4930
		56	4850
57	4930
		58	4890
59	4790
		60	4920
61	4880
		62	4870
63	4910
		64	4790
65	4930
		66	4790
67	4880
		68	4850
69	4870
		70	4920

71	4910
		72	4860
73	4880
		Comparative example 2	3810

Conclusion: above-mentioned test result shows, with AgPd50 alloy phase ratio, Pd-Ag-Cu-RE alloy of the present invention and Pd-Ag-Cu-RE-AM alloy have better wear resistance and electrical contact performance, with it as working lining and copper or the compound composite material of making of copper alloy, be used to make DC motor brush sheet, compare with the electrical micro-machine brush sheet that adopts AgPd50 alloy made, with the condition of the commutator of identical material and specification pairing operation under, demonstrate longer useful life, reach the purpose that improves DC motor working life and stability, thereby more effectively given play to the premium properties of noble metal contact material.

Present embodiment be with palladium-silver be alloy as electric contact material as working lining, copper alloy is as basic unit.According to above-mentioned, those skilled in the art can be that alloy as electric contact material is as working lining with palladium-silver according to production technology of the present invention fully, copper obtains being used for the two-layer laminar composite that slidingtype electrically contacts as basic unit, and the composite material of gained has technique effect of the present invention equally.

For reducing production costs, present embodiment is the Alba alloy layer segment to be compounded in copper or the copper alloy basic unit (part is compound to be at the compound Alba alloy in working region that is used for the two-layer laminar composite that slidingtype electrically contacts), according to above-mentioned, those skilled in the art fully can according to production technology of the present invention just the Alba alloy layer all be compounded in copper or the copper alloy basic unit, what obtain is used for the two-layer laminar composite that slidingtype electrically contacts, and the composite material of gained has technique effect of the present invention equally.

Claims

1. a palladium-silver that is used for DC motor brush sheet is a contact material, it is characterized in that described material is made up of Pd, Cu, RE, Ag, and each composition percentage composition by weight is:

Pd 40-48%；

Cu 1-10%；

RE 0.05-1%；

Surplus is Ag;

Wherein, RE is one or more in La, Ce, Nd, Sm, Eu, Gd, the Er element.

2. a palladium-silver that is used for DC motor brush sheet is a contact material, and it is characterized in that: described material is made up of Pd, Cu, RE, AM, Ag, and each composition percentage composition by weight is:

Pd 40-48%；

Cu 1-10%；

RE 0.05-1%；

AM 0.05-0.5%；

Surplus is Ag;

3. be used for the two-layer laminar composite that slidingtype electrically contacts, it is characterized in that: by claim 1 or the described palladium-silver of claim 2 is contact material and copper or the compound composite material that obtains of copper alloy, wherein palladium-silver be alloy as electric contact material as working lining, copper or copper alloy are as basic unit.

4. composite material according to claim 3 is characterized in that: the Alba alloy layer segment all be compounded in copper or copper alloy basic unit on.

5. brush plate with claim 3 or the preparation of 4 described laminar composites.

6. a DC motor is used the described brush plate of claim 5.