
JIS G4313
Cold rolled stainless steel strip for springs
Stainless steel, also known as inox, corrosion-resistant steel (CRES) and rustless steel, is an alloy of iron that is resistant to rusting and corrosion. It's resistance to corrosion results from the chromium, which forms a passive film that can protect the material and self-heal in the presence of oxygen.
Symbol of grade
|
C
|
Si
|
Mn
|
P
|
S
|
Ni
|
Cr
|
SUS 301-CSP
|
0.15 max.
|
1.00 max.
|
2.00 max.
|
0.045 max.
|
0.030 max.
|
6.00 to 8.00
|
16.00 to 18.00
|
SUS 304-CSP
|
0.08 max.
|
1.00 max.
|
2.00 max.
|
0.045 max.
|
0.030 max.
|
8.00 to 10.50
|
18.00 to 20.00
|
Symbol of grade
|
C
|
Si
|
Mn
|
P
|
S
|
Cr
|
SUS 420J2-CSP
|
0.26 to 0.40
|
1.00 max.
|
1.00 max.
|
0.040 max.
|
0.030 max.
|
12.00 to 14.00
|
Remarks: It may contain 0.60% or less of Ni.
Symbol of grade
|
C
|
Si
|
Mn
|
P
|
S
|
Ni
|
Cr
|
Cu
|
Others
|
SUS 631-CSP
|
0.09 max.
|
1.00 max.
|
1.00 max.
|
0.040 max.
|
0.030 max.
|
6.50 to 7.75
|
16.00 to 18.00
|
- |
Al 0.75 to 1.50
|
SUS 632J1-CSP
|
0.09 max.
|
1.00 to 2.00
|
1.00 max.
|
0.040 max.
|
0.030 max.
|
6.50 to 7.75
|
13.50 to 15.50
|
0.40 to 1.00
|
Ti 0.20 to 0.65
|
Symbol of grade
|
Symbol of temper
|
As cold rolled, or eighter as solution-treated or as annealed
|
As precipitation-hardened
|
||
Hardness HV
|
Bendability
V-bend |
Symbol of beat treatment
|
Hardness HV
|
||
SUS 301-CSP
|
1/2 H
|
310 min.
|
Twice the thickness at most
|
- | - |
|
3/4 H
|
370 min.
|
2.5 times the thickness at most
|
- | - |
|
H
|
430 min.
|
- | - | - |
|
EH
|
490 min.
|
- | - | - |
|
SEH(
1
)
|
530 min.
|
- | - | - |
SUS 304-CSP
|
1/2 H
|
250 min.
|
Twice the thickness at most
|
- | - |
3/4 H
|
310 min.
|
2.5 times the
thickness at most |
- | - | |
H
|
370 min.
|
- | - | - | |
SUS 420J2-CSP
|
0
|
247 max.
|
- | - | - |
SUS 631-CSP
|
0
|
200 max.
|
0.5 times the thickness at most
|
TH1050
RH950 |
345 min.
392 min. |
1/2 H
|
350 min.
|
1.5 times the thickness at most
|
CH
|
380 min.
|
|
3/4 H
|
400 min.
|
- |
CH
|
450 min.
|
|
SUS 632J1-CSP
|
1/2 H
|
350 min.
|
- |
CH
|
400 min.
|
3/4 H
|
420 max.
|
- |
CH
|
480 min.
|
Note (1) The temper symbol SEH denotes that this is within the range specified as the temper symbol EH, and it shall be applied
when especially designated by the purchaser.
Remarks:
1. The bendability is given by the inside radius, and the angle of bending shall be 90°. The bend test shall be applied when designated by the purchaser.
2. The precipitation hardening heat treatment for SUS 631-CSP shall be as specified below:
(1) For the strip with temper symbol 0:
TH1050: After solution treatment (1000℃ to 1100℃, rapid cooling), hold at 760 ±15℃ for 90 min, cool down to 15℃ or below within 1 h, hold for 30 min, hold at 565 ± 10℃ for 90 min and air-cool.
RH950: After solution treatment (1000℃ to 1100℃, rapid cooling), hold at 955 ± 10℃ for 10 min, air-cool down to room temperature, cool down to -73 ±6℃ within 24 h, hold for 8 h, hold at 510 ± 10℃ for 60 min and air-cool.
(2) For the strip with temper symbol 1/2H, 3/4H, and H:
CH: Hold at 475±10℃ for 1h and air-cool.
3. The precipitation hardening heat treatment for SUS 632J1-CSP SHALL BE AS SPECIFIED BELOW:
CH: Hold at 475 ± 10℃ for 1 h and air-cool.
4. The annealing for SUS 420J2-CSP (for temper symbol 0) shall be as specified below:
Air-cool at about 750℃ or slow-cool at 800 to 900 C.
Thickness
|
Width tolerance (Unit: mm)
|
|||
Width
Less than 80 |
Width
80 and over, to and excl. 160 |
Width
160 and over, to and excl.250 |
Width
250 and over, to and excl.600 |
|
Less than 0.60
|
±0.10
|
±0.15
|
±0.20
|
±0.25
|
0.60 and over, to and excl. 1.00
|
±0.15
|
±0.20
|
±0.25
|
±0.25
|
1.00 and over, up to and incl. 1.60
|
±0.20
|
±0.20
|
±0.30
|
±0.30
|
Width
|
Maximum value of camber in any length of 1 m
|
10 and over, to and excl. 20
|
8 |
20 and over, to and excl. 40
|
6 |
40 and over, to and excl. 80
|
3 |
80 and over
|
1 |
Remarks: The figures in Table 10 shall be applied to the strip having the ratio (W/T) of 10 or over with (W) and (T) defined as the
width and the thickness, respectively.