METAL MATERIAL FOR A WIRING CONNECTOR

Abstract

A metal material for a wiring connector in wiring connection between metallic members, wherein at least one of the metallic members is comprised of copper or a copper alloy, wherein a connecting portion surface of at least one of the metallic members has an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2.0 μm or less, and wherein the metal material is excellent in glow resistance.

Description

TECHNICAL FIELD

The present invention relates to a metal material for a wiring connector in which at least one metallic member of the wiring connector is comprised of copper or a copper alloy material. More specifically, the present invention relates to a metal material for a wiring connector capable of preventing occurrence of glow and proliferation of cuprous oxide.

BACKGROUND ART

A wiring connector has been widely used for a potion of electric connection, e.g. an outlet of an electrical appliance or a switch of illumination. A metal is generally used for the connecting portion, and metals are brought into contact with each other to carry out electric connection. Hitherto, heat generation at the connecting portion has been of concern. It has been known that micro-electric discharge (glow) occurs at a connecting portion, and proliferation of cuprous oxide is induced by the micro-electric discharge, to increase a contact resistance, thereby resulting in heat generation.

There has been proposed a copper alloy for a wiring connector with its alloy component reviewed so that said glow and proliferation of cuprous oxide hardly occur.

However, even investigation into an alloy component cannot prevent heat generation due to the occurrence of glow and the proliferation of cuprous oxide.

DISCLOSURE OF INVENTION

The inventors of the present invention, having made extensive studies on a connecting portion of a wiring connector, found that a roughness (degree of roughness) of a surface of a material and occurrence of glow are related to each other. The inventors have made further studies based on this finding, to attain the present invention.

According to the present invention, the following means are provided:

(1) A metal material for a wiring connector in wiring connection between metallic members, wherein at least one of the metallic members is comprised of copper or a copper alloy, wherein a connecting portion surface of at least one of the metallic members has an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2.0 μm or less, and wherein the metal material is excellent in glow resistance; and

(2) The metal material for a wiring connector according to the above item (1), wherein a ratio Rt/Ra between the maximum roughness Rt and the average roughness Ra is 10 or less, and wherein the metal material is excellent in glow resistance.

In the metal material for a wiring connector of the present invention, the average roughness Ra and the maximum roughness Rt are limited, and, preferably, a ratio of the maximum roughness Rt to the average roughness Ra is controlled in the above-mentioned range. As a result, occurrence of glow and proliferation of cuprous oxide can be prevented, and heat generation can be suppressed. Therefore, the metal material is suitable for a wiring connector, such as an outlet of an electrical appliance, or a switch of illumination.

Other and further features and advantages of the invention will appear more fully from the following description, taken in connection with the accompanying drawing.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a schematic view of an apparatus for measuring glow resistance and cuprous oxide proliferation resistance, which apparatus was used in the following example.

BEST MODE FOR CARRYING OUT THE INVENTION

A preferred embodiment of the present invention will be described in detail. In the present invention, roughness is defined in accordance with JIS B 0601:2001. That is, the average roughness Ra in the present invention refers to the arithmetic average roughness of JIS B 0601:2001 mentioned above, and, similarly, the maximum roughness Rt in the present invention refers to the maximum sectional height of the roughness curve of JIS B 0601:2001 mentioned above.

In the present invention, at least one of the metallic members in wiring connection between the metallic members is comprised of copper or a copper alloy.

In the present invention, the surface at the connecting portion (contact point) of at least one of the metallic members, has an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2 μm or less, and the metallic members preferably each have an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2 μm or less.

The present invention include the case in which a metallic member having an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2 μm or less is comprised of copper or a copper alloy, and the case in which such metallic member is comprised of not copper or a copper alloy but other metal material e.g. an Ni alloy.

The average roughness Ra of 0.3 μm or less and maximum roughness Rt of 2 μm or less are preferable because occurrence of glow can be drastically reduced.

A degree of roughness is an indication for irregularities of the surface of a material. It is assumed that voltages applied to the tips of the irregularities may converge to cause glow discharge.

In the present invention, when the average roughness Ra is more than 0.3 μm, it results that glow discharge be apt to occur. The average roughness Ra is preferably 0.2 μm or less.

On the other hand, similarly to the above, when the maximum roughness Rt is more than 2 μm, it results that glow discharge be apt to occur. The maximum roughness Rt is preferably 1 μm or less.

The average roughness Ra and maximum roughness Rt are preferably as small as possible. The lower limits of said average roughness Ra and maximum roughness Rt are not limited in particular, but generally the average roughness Ra is preferably 0.01 μm or more, and generally the maximum roughness Rt is preferably 0.05 μm or more.

The ratio Rt/Ra of the maximum roughness Rt to the average roughness Ra in the present invention is preferably 10 or less.

When the ratio Rt/Ra of the maximum roughness Rt to the average roughness Ra is 10 or less, occurrence of glow can be more effectively reduced. It is assumed that when the Rt/Ra is too large, it causes a site having large irregularities to be locally present so that glow discharge may be apt to occur at the site.

In the present invention, the ratio Rt/Ra is preferably 5 or less. The ratio Rt/Ra is preferably as small as possible. The lower limit of said ratio Rt/Ra is not limited in particular, but generally the ratio Rt/Ra is preferably 2 or more.

Any one of metals excellent in mechanical strength and electric conductivity is generally used for the metal material of the present invention for a wiring connector, because the metal material is required to have a contact pressure and electrical conductivity at a contact point. Of such metals, a stainless steel, a Ni alloy, and a copper alloy are preferable because they are excellent in mechanical strength and conductivity. It is more preferable that the metal material has a tensile strength of 500 MPa or more and/or a conductivity of 30% IACS or more.

Examples of the more preferable metal material include:

• (1) a copper alloy comprising Sn 0.1 to 10 mass %, and P 0.001 to 0.5 mass %, the balance being copper and an inevitable impurity(s);
• (2) a copper alloy comprising Cr 0.1 to 1.0 mass %, and 0.05 to 5 mass % of at least one element of Sn and Zn, the balance being copper and an inevitable impurity(s);
• (3) a copper alloy comprising Ni 1.0 to 5.0 mass %, Si 0.3 to 1.3 mass %, and 0.05 to 5.0 mass % in total of at least one element of Mg, Sn, and Zn, the balance being copper and an inevitable impurity(s); and
• (4) a copper alloy comprising Fe 0.5 to 3.0 mass %, and P 0.1 to 1.0 mass %, the balance being copper and an inevitable impurity(s).

The metal material for a wiring connector of the present invention can be produced by means of a general production method involving appropriate repetition, for example, of casting, hot-rolling, cold-rolling, and heat-treating. Further, the average roughness Ra and maximum roughness Rt can be controlled by washing the surface of the metal material with an acid, an alkali, or the like, or by changing the degree of roughness of a roll in a cold-rolling step.

EXAMPLE

The present invention will be described in more detail based on examples given below, but the invention is not meant to be limited by these.

Commercially available sheet materials each composed of a copper alloy or non-ferrous material with thickness 0.15 to 0.25 mm were obtained, and tensile strength, hardness, and conductivity of them were measured. Regarding tensile strength, a JIS-5 test piece was cut out from a direction parallel to the direction rolled, and its tensile strength was measured in accordance with JIS Z 2241. The hardness of the surface of the material was measured in accordance with JIS Z 2244 under a load of 100 g-wt. Regarding electrical conductivity (EC), a test piece with width 10-mm and length 150-mm was cut out from a direction parallel to the direction rolled, and its electrical conductivity was measured in accordance with JIS H 3200 with a distance between terminals of 100 mm. Tables 1 and 2 show the results. Please note that some of the samples given below had different values of mechanical strength, hardness, and electric conductivity, even though they had the same alloy composition, which was resulted due to the fact that their tempers or production conditions were not same each other.

TABLE 1
Sheet
material	Main component	Strength	Hardness	EC
No.	mass %	MPa	Hv	% IACS
1	Cu—0.15Sn	443	150	88
2	Cu—3.9Sn—0.15P	422	144	19
3	Cu—3.9Sn—0.15P	655	217	17
4	Cu—5.8Sn—0.12P	688	227	14
5	Cu—7.9Sn—0.2P	721	237	13
6	Cu—21Zn	412	141	34
7	Cu—32Zn	482	163	28
8	Cu—32Zn	610	203	28
9	Cu—0.55Cr	582	194	74
10	Cu—0.29Cr—0.25Sn—0.5Zn	550	184	77
11	Cu—0.28Cr—0.8Sn—0.45Zn	528	177	55
12	Cu—0.28Cr—0.8Sn—0.45Zn	668	221	52
13	Cu—0.3Cr—2Sn	685	226	41
14	Cu—0.21Cr—0.11Zr—0.2Zn	522	175	22
15	Cu—2.6Ni—0.55Si—0.1Mg	567	189	75
16	Cu—2.3Ni—0.5Si—0.1Mg—0.15Sn—0.5Zn	680	225	42
17	Cu—2.3Ni—0.5Si—0.1Mg—0.15Sn—0.5Zn	722	238	41
18	Cu—3.7Ni—0.9Si—0.1Mg—0.15Sn—0.5Zn	815	267	35
19	Cu—2.5Ni—0.55Si	712	235	41
20	Cu—2.5Ni—0.55Si—0.5Zn	734	241	48
201	Cu—0.25Cr—0.77Sn—0.3Zn	670	231	51
202	Cu—0.25Cr—0.77Sn—0.3Zn	693	241	51
203	Cu—0.3Cr—0.84Sn—0.4Zn	681	235	50
204	Cu—0.3Cr—0.84Sn—0.4Zn	702	250	50

TABLE 2
Sheet
material	Main component	Strength	Hardness	EC
No.	mass %	MPa	Hv	% IACS
21	Cu—0.1Fe—0.04P	422	144	90
22	Cu—1Fe—0.5Sn—0.5Zn	534	179	55
23	Cu—2.4Fe—0.2P	534	179	64
24	Cu—1Ni—0.05P—0.9Sn	523	175	38
25	Cu—0.8Mg—0.05P	511	172	61
26	Cu—3.8Ti	882	288	11
27	Cu—0.15Ag	515	173	96
28	Cu—0.15Zr	498	168	94
29	Cu—0.2Be—1.1Ni	783	257	37
30	Cu—0.2Fe—0.05P—0.96Sn—0.1Ni—0.03B	511	172	75
31	Cu—0.1Fe—0.1Ni—0.05P—0.11Ni—0.04B	533	179	34
32	Cu—3.1Ni—0.68Si—0.3Zn	588	196	54
33	Cu—2.1Sn—0.1Fe—0.03P	562	188	35
34	Cu—2.1Ni—0.53Si—1Zn—0.5Sn	641	212	38
35	Cu—25Zn—0.6Sn	882	288	22
36	Al—0.4Si—0.4Fe—0.1Cu—0.33Mn—4.2Mg—0.1Cr	320	112	18
37	Fe—17Cr—7Ni	1823	582	4
38	Fe—18Cr—8Ni	1432	460	6
39	Fe—36Ni	634	210	3
40	Ni	622	206	18

The surface of the sheet materials was abraded with emery papers (abrasive papers having abrasive particles of SiC adhering to the papers' surface) of various counts of yarn in the same direction as the direction rolled, i.e. the direction parallel to the direction rolled, to obtain materials different from each other in surface roughness. That is, a sample sheet material was fixed on a smooth platen and abraded with emery paper, whose count of yarn was sequentially increased from #230 to #4,000 in eight stages, 30 times in the number of abrasion, and then the resultant surface was washed. It was judged that the abrasion could remove cuprous oxide on a surface layer, and the resultant was subjected to the following evaluation.

A surface roughness was measured in accordance with JIS H 3406. A sample material was scanned with a stylus (probe) by 4 mm in a direction perpendicular to the direction in which the material was abraded with emery papers or the direction rolled. The measurement was repeated three times, and the average value of the measurements was determined.

The resultant sheet materials were evaluated for glow resistance and cuprous oxide proliferation resistance.

FIG. 1 shows a schematic view of an apparatus for measuring glow resistance and cuprous oxide proliferation resistance.

Evaluation for glow resistance was performed as described below. That is, a copper wire 2 with diameter 2 mm was attached to a holder 1 equipped with a load applier, and a sample 3 of any one of the examples according to the present invention or the comparative examples was placed on a sample holder 4. Then, the sample was brought into contact with the copper wire 2, and a current flowing between the copper wire 2 and the sample 3 was adjusted to 4A, by means of Slidac (an autotransformer, trade name, manufactured by Toshiba) 8 and a variable resistor 6. Then, the sample holder 4 was vibrated with a vibrator 5, and the wave form of a voltage between the copper wire 2 and the sample 3 was observed with an oscilloscope 7. When glow (micro-electric discharge) occurred between the copper wire 2 and the sample 3, it changed the wave form on the oscilloscope 7. A frequency (the number of times vibrated) applied until the occurrence of the change in wave form was utilized to evaluate glow resistance. With respect to evaluation of grow resistance, when the number of vibration applied until occurrence of the change in wave form, which means occurrence of grow, is 1,000 or less, it is judged to be “poor”; when said number is more than 1,000 but not more than 2,000, it is judged to be “satisfactory”; and when said number is more than 2,000, it is judged to be “good”.

Then, evaluation for cuprous oxide proliferation resistance was performed as described below. Vibration with the vibrator 5 was stopped simultaneously with the confirmation of the occurrence of glow, and then the sample 3 was left to stand for 60 minutes. Then, the sample 3 was taken out, and then cuprous oxide formed on the surface of the sample 3 was collected, to measure the mass thereof. The mass, i.e. the proliferated amount of cuprous oxide (mg), was utilized to evaluate cuprous oxide proliferation resistance. With respect to evaluation of cuprous oxide proliferation resistance, when the mount of cuprous oxide formed (mg) is 200 mg or less, it is judged to be “good”; when said amount is more than 200 mg but not more than 250 mg, it is judged to be “satisfactory”; and when said amount is more than 250 mg, it is judged to be “poor”.

Tables 3 to 7 show the results.

TABLE 3
					Glow	Cuprous
					resist-	oxide
	Sheet				ance	proliferation
	material	Ra	Rt		×1,000	resistance
No.	No.	μm	μm	Rt/Ra	(times)	(mg)	Remarks
1	1	0.12	0.82	6.83	200	153	This
2	1	0.21	1.71	8.14	65	83	invention
3	2	0.15	1.23	8.04	128	133
4	2	0.17	1.39	8.11	46	76
5	3	0.12	1.05	8.75	212	155
6	3	0.22	1.77	8.01	73	95
7	4	0.19	1.52	7.97	221	157
8	4	0.23	1.84	8.18	61	80
9	5	0.16	1.31	8.09	29	70
10	5	0.16	1.35	8.29	131	120
11	6	0.22	1.69	7.79	172	146
12	6	0.16	1.34	8.17	87	96
13	7	0.20	1.65	8.32	330	181
14	7	0.17	1.30	7.73	77	80
15	8	0.14	1.11	7.93	34	76
16	8	0.18	1.44	7.84	54	82
17	9	0.05	0.48	8.93	97	122
18	9	0.18	1.39	7.60	80	87
19	10	0.07	0.51	7.49	419	180
20	10	0.27	1.88	7.97	29	48
21	11	0.07	0.62	8.72	153	141
22	11	0.25	2.00	8.02	43	65
23	12	0.07	0.52	7.91	113	128
24	12	0.30	1.92	8.02	125	99
25	13	0.07	0.60	8.01	51	94
26	13	0.22	1.56	7.20	180	127
27	14	0.05	0.43	7.84	127	133
28	14	0.24	1.84	7.83	238	139
29	15	0.09	0.65	7.45	308	171
30	15	0.16	1.29	8.07	25	43

TABLE 4
					Glow	Cuprous
					resist-	oxide
	Sheet				ance	proliferation
	material	Ra	Rt		×1,000	resistance
No.	No.	μm	μm	Rt/Ra	(times)	(mg)	Remarks
31	16	0.02	0.14	7.03	343	80	This
32	16	0.12	0.97	8.39	90	127	invention
33	17	0.06	0.52	8.01	263	165
34	17	0.13	1.09	8.56	40	62
35	18	0.01	0.06	4.95	125	155
36	18	0.20	1.67	8.24	215	93
37	19	0.04	0.24	6.54	38	81
38	19	0.25	1.92	7.83	54	127
39	20	0.02	0.22	9.12	242	87
40	20	0.27	1.89	7.05	32	53
41	21	0.11	0.92	8.37	100	111
42	21	0.21	1.65	7.88	82	88
43	22	0.08	0.58	7.40	69	119
44	22	0.16	1.20	7.50	32	62
45	23	0.11	0.89	7.84	33	62
46	23	0.14	1.21	8.33	37	68
47	24	0.18	1.42	7.93	48	79
48	24	0.16	1.38	8.46	41	72
49	25	0.20	1.57	7.95	213	89
50	25	0.14	1.16	8.15	42	73
51	26	0.12	0.99	8.03	116	117
52	26	0.21	1.70	8.10	27	54
53	27	0.13	1.06	8.40	131	135
54	27	0.21	1.69	7.90	127	79
55	28	0.06	0.48	7.77	196	152
56	28	0.22	1.76	8.16	94	87
57	29	0.01	0.05	9.33	263	149
58	29	0.28	1.87	6.75	248	156
59	30	0.05	0.47	9.32	379	181
60	30	0.26	1.99	7.55	154	120
601	201	0.11	1.25	11.36	221	155
602	202	0.14	1.38	9.86	123	131
603	203	0.13	1.05	8.08	112	120
604	204	0.18	1.18	6.56	104	115

TABLE 5
					Glow	Cuprous
					resist-	oxide
	Sheet				ance	proliferation
	material	Ra	Rt		×1,000	resistance
No.	No.	μm	μm	Rt/Ra	(times)	(mg)	Remarks
61	31	0.05	0.46	9.69	162	137	This
62	31	0.24	1.89	7.86	196	131	invention
63	32	0.03	0.25	7.44	188	161
64	32	0.18	1.38	7.78	185	140
65	33	0.08	0.61	7.94	352	181
66	33	0.22	1.92	8.86	108	105
67	34	0.15	1.31	8.62	190	143
68	34	0.19	1.81	9.44	102	110
69	35	0.11	0.91	8.37	92	119
70	35	0.20	1.36	6.92	34	55
71	36	0.18	1.49	8.08	68	106
72	36	0.28	1.85	3.83	398	162
73	37	0.12	0.88	7.45	30	70
74	37	0.17	1.89	4.04	175	126
75	38	0.09	0.64	6.94	42	85
76	38	0.21	1.87	4.43	64	75
77	39	0.17	1.35	7.94	41	84
78	39	0.25	1.64	6.67	218	136
79	40	0.20	1.56	7.97	175	147
80	40	0.28	1.92	6.77	68	93
81	3	0.23	1.93	8.36	212	155
82	7	0.23	1.88	8.25	114	101
83	14	0.29	1.85	6.28	114	113
84	18	0.23	1.97	8.41	123	136

TABLE 6
					Glow	Cuprous
					resist-	oxide
	Sheet				ance	proliferation
	material	Ra	Rt		×1,000	resistance
No.	No.	μm	μm	Rt/Ra	(times)	(mg)	Remarks
85	1	0.35	2.84	8.11	9.3	394	Compar-
86	2	0.41	3.24	7.91	2.0	354	ative
87	4	0.35	2.54	7.31	0.7	322	example
88	5	0.47	3.76	7.96	2.3	320
89	6	0.41	4.03	9.80	0.7	288
90	8	0.54	4.25	7.91	5.9	374
91	9	0.40	4.35	11.01	2.3	361
92	10	0.59	4.71	8.02	2.1	367
93	11	0.26	4.00	15.28	5.1	386
94	12	0.58	4.70	8.11	3.2	348
95	13	0.56	4.48	8.06	1.5	316
96	15	0.34	2.52	7.39	5.4	350
97	16	0.32	2.70	8.46	3.0	395
98	17	0.57	4.52	7.87	0.7	328
99	19	0.33	2.94	8.99	0.7	302
100	20	0.48	3.88	8.04	4.5	385

TABLE 7
					Glow	Cuprous
					resist-	oxide
	Sheet				ance	proliferation
	material	Ra	Rt		×1,000	resistance
No.	No.	μm	μm	Rt/Ra	(times)	(mg)	Remarks
101	21	0.39	3.20	8.22	3.3	327	Compar-
102	22	0.21	3.35	15.75	1.2	332	ative
103	23	0.22	3.36	15.23	1.0	311	example
104	24	0.44	2.54	5.72	3.4	328
105	25	0.23	3.45	15.05	8.2	366
106	26	0.13	2.41	18.28	2.0	305
107	27	0.49	3.86	7.93	6.1	375
108	28	0.23	2.90	12.55	6.1	376
109	29	0.26	2.89	11.08	5.8	377
110	30	0.45	3.62	8.00	0.9	422
111	31	0.36	3.11	8.53	1.8	330
112	32	0.41	3.28	8.02	3.8	404
113	33	0.28	3.81	13.73	5.9	407
114	34	0.45	3.57	7.90	9.5	428
115	35	0.49	3.96	8.04	8.7	410
116	36	0.29	3.92	13.60	3.8	365
117	37	0.27	3.57	13.02	1.1	320
118	38	0.33	2.70	8.18	9.0	425
119	39	0.64	5.16	8.04	0.7	378
120	40	0.70	5.60	8.01	1.2	340

As is apparent from Tables 3 to 7, the sheet materials Nos. 85-to 120 for comparison each had a too large Ra or too large Ra and Rt, so they showed a conspicuously large amount of cuprous oxide proliferated, or alternatively, they were poor in glow resistance and showed a conspicuously large amount of cuprous oxide proliferated.

Contrary to the above, it is found that the sheet materials of the present invention shown in Nos. 1 to 84 and 601 to 604 each were excellent, since they each were excellent in glow resistance and showed a drastically small amount of cuprous oxide proliferated.

INDUSTRIAL APPLICABILITY

In the metal material of the present invention for a wiring connector, the average roughness Ra and the maximum roughness Rt are limited, and, preferably, a ratio of the maximum roughness Rt to the average roughness Ra is controlled in a prescribed range. As a result, occurrence of glow and proliferation of cuprous oxide can be prevented, and heat generation can be suppressed. Therefore, the metal material of the present invention is preferable for use in a wiring connector, such as an outlet of an electrical appliance, or a switch of illumination.

Having described our invention as related to the present embodiments, it is our intention that the invention not be limited by any of the details of the description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

Claims

1. A metal material for a wiring connector in wiring connection between metallic members, wherein at least one of the metallic members is comprised of copper or a copper alloy, wherein a connecting portion surface of at least one of the metallic members has an average roughness Ra of 0.3 μm or less and a maximum roughness Rt of 2.0 μm or less, and wherein the metal material is excellent in glow resistance.

2. The metal material for a wiring connector as claimed in claim 1, wherein a ratio Rt/Ra between the maximum roughness Rt and the average roughness Ra is 10 or less, and wherein the metal material is excellent in glow resistance.

3. The metal material for a wiring connector as claimed in claim 1, wherein the metal material has a tensile strength of 500 MPa or more, and an electric conductivity of 30% IACS or more.

4. The metal material for a wiring connector as claimed in claim 1, wherein the metal material is comprised of a copper alloy comprising Sn 0.1 to 10 mass %, and P 0.001 to 0.5 mass %, the balance being copper and inevitable impurities.

5. The metal material for a wiring connector as claimed in claim 1, wherein the metal material is comprised of a copper alloy comprising Cr 0.1 to 1.0 mass %, and 0.05 to 5 mass % of at least one element of Sn and Zn, the balance being copper and an inevitable impurities.

6. The metal material for a wiring connector as claimed in claim 1, wherein the metal material is comprised of a copper alloy comprising Ni 1.0 to 5.0 mass %, Si 0.3 to 1.3 mass %, and 0.05 to 5.0 mass % in total of at least one element of Mg, Sn, and Zn, the balance being copper and an inevitable impurities.

7. The metal material for a wiring connector as claimed in claim 1, wherein the metal material is comprised of a copper alloy comprising Fe 0.5 to 3.0 mass %, and P 0.1 to 1.0 mass %, the balance being copper and an inevitable impurities.

8. The metal material for a wiring connector as claimed in claim 2, wherein the metal material has a tensile strength of 500 MPa or more, and an electric conductivity of 30% IACS or more.

9. The metal material for a wiring connector as claimed in claim 2, wherein the metal material is comprised of a copper alloy comprising Sn 0.1 to 10 mass %, and P 0.001 to 0.5 mass %, the balance being copper and inevitable impurities.

10. The metal material for a wiring connector as claimed in claim 2, wherein the metal material is comprised of a copper alloy comprising Cr 0.1 to 1.0 mass %, and 0.05 to 5 mass % of at least one element of Sn and Zn, the balance being copper and an inevitable impurities.

11. The metal material for a wiring connector as claimed in claim 2, wherein the metal material is comprised of a copper alloy comprising Ni 1.0 to 5.0 mass %, Si 0.3 to 1.3 mass %, and 0.05 to 5.0 mass % in total of at least one element of Mg, Sn, and Zn, the balance being copper and an inevitable impurities.

12. The metal material for a wiring connector as claimed in claim 2, wherein the metal material is comprised of a copper alloy comprising Fe 0.5 to 3.0 mass %, and P 0.1 to 1.0 mass %, the balance being copper and an inevitable impurities.