Descripción del producto
Background
Grade **4 is the standard "*8/8" stainless; it is the most
versatile and most widely used stainless steel, available in a
wider range of products, forms and finishes than any other. It
has excellent forming and welding characteristics. The balanced
austenitic structure of Grade **4 enables it to be severely deep
drawn without intermediate annealing, which has made this grade
dominant in the manufacture of drawn stainless parts such as
sinks, hollow-ware and saucepans. For these applications it is
common to use special "**4DDQ" (Deep Drawing Quality) variants.
Grade **4 is readily brake or roll formed into a variety of
components for applications in the industrial, architectural, and
transportation fields. Grade **4 also has outstanding welding
characteristics. Post-weld annealing is not required when welding
thin sections.
Grade **4L, the low carbon version of **4, does not require
post-weld annealing and so is extensively used in heavy gauge
components (over about 6mm). Grade **4H with its higher carbon
content finds application at elevated temperatures. The
austenitic structure also gives these grades excellent toughness,
even down to cryogenic temperatures.
Key Properties
These properties are specified for flat rolled product (plate,
sheet and coil) in ASTM A**0/A**0M. Similar but not necessarily
identical properties are specified for other products such as
pipe and bar in their respective specifications.
Composition
Typical compositional ranges for grade **4 stainless steels are
given in table 1.
Table 1. Composition ranges for **4 grade stainless steel
Grade
C
Mn
Si
P
S
Cr
Mo
Ni
N
**4
min.
max.
-
0.*8
-
2.0
-
0.*5
-
0.**5
-
0.**0
*8.0
*0.0
-
8.0
*0.5
-
0.*0
**4L
min.
max.
-
0.**0
-
2.0
-
0.*5
-
0.**5
-
0.**0
*8.0
*0.0
-
8.0
*2.0
-
0.*0
**4H
min.
max.
0.*4
0.*0
-
2.0
-
0.*5
*0.**5
-
0.**0
*8.0
*0.0
-
8.0
*0.5
-
Mechanical Properties
Typical mechanical properties for grade **4 stainless steels are
given in table 2.
Table 2. Mechanical properties of **4 grade stainless steel
Grade
Tensile Strength (MPa) min
Yield Strength 0.2% Proof (MPa) min
Elongation (% in *0mm) min
Hardness
Rockwell B (HR B) max
Brinell (HB) max
**4
**5
**5
*0
*2
**1
**4L
**5
**0
*0
*2
**1
**4H
**5
**5
*0
*2
**1
**4H also has a requirement for a grain size of ASTM No 7 or
coarser.
Physical Properties
Typical physical properties for annealed grade **4 stainless
steels are given in table 3.
Table 3. Physical properties of **4 grade stainless steel in the
annealed condition
Grade
Density (kg/m3)
Elastic Modulus (GPa)
Mean Coefficient of Thermal Expansion (mm/m/°C)
Thermal Conductivity (W/m.K)
Specific Heat ****0°C (J/kg.K)
Electrical Resistivity (nW.m)
****0°C
****5°C
****8°C
at **0°C
at **0°C
**4/L/H
***0
**3
*7.2
*7.8
*8.4
*6.2
*1.5
**0
**0
Grade Specification Comparison
Approximate grade comparisons for **4 stainless steels are given
in table 4.
Table 4. Grade specifications for **4 grade stainless steel
Grade
UNS No
Old British
Euronorm
Swedish SS
Japanese JIS
BS
En
No
Name
**4
S****0
**4S*1
*8E
1.***1
X5CrNi****0
***2
SUS **4
**4L
S****3
**4S*1
-
1.***6
X2CrNi****1
***2
SUS **4L
**4H
S****9
**4S*1
-
1.***8
X6CrNi****1
-
-
These comparisons are approximate only. The list is intended as a
comparison of functionally similar materials not as a schedule of
contractual equivalents. If exact equivalents are needed original
specifications must be consulted.
Possible Alternative Grades
Possible alternative grades to grade **4 stainless steels are
given in table 5.
Table 5. Possible alternative grades to **4 grade stainless steel
Grade
Why it might be chosen instead of **4
**1L
A higher work hardening rate grade is required for certain roll
formed or stretch formed components.
**2HQ
Lower work hardening rate is needed for cold forging of screws,
bolts and rivets.
**3
Higher machinability needed, and the lower corrosion resistance,
formability and weldability are acceptable.
**6
Higher resistance to pitting and crevice corrosion is required,
in chloride environments
**1
Better resistance to temperatures of around ******0°C is
needed…**1 has higher hot strength.
3CR*2
A lower cost is required, and the reduced corrosion resistance
and resulting discolouration are acceptable.
**0
A lower cost is required, and the reduced corrosion resistance
and fabrication characteristics are acceptable.
Corrosion Resistance
Excellent in a wide range of atmospheric environments and many
corrosive media. Subject to pitting and crevice corrosion in warm
chloride environments, and to stress corrosion cracking above
about *0°C. Considered resistant to potable water with up to
about **0mg/L chlorides at ambient temperatures, reducing to
about **0mg/L at *0°C.
Heat Resistance
Good oxidation resistance in intermittent service to **0°C and in
continuous service to **5°C. Continuous use of **4 in the
******0°C range is not recommended if subsequent aqueous
corrosion resistance is important. Grade **4L is more resistant
to carbide precipitation and can be heated into the above
temperature range.
Grade **4H has higher strength at elevated temperatures so is
often used for structural and pressure-containing applications at
temperatures above about **0°C and up to about **0°C. **4H will
become sensitised in the temperature range of ******0°C; this is
not a problem for high temperature applications, but will result
in reduced aqueous corrosion resistance.
Heat Treatment
Solution Treatment (Annealing) - Heat to ********0°C and cool
rapidly. These grades cannot be hardened by thermal treatment.
Welding
Excellent weldability by all standard fusion methods, both with
and without filler metals. AS ***4.6 pre-qualifies welding of **4
with Grade **8 and **4L with **8L rods or electrodes (and with
their high silicon equivalents). Heavy welded sections in Grade
**4 may require post-weld annealing for maximum corrosion
resistance. This is not required for Grade **4L. Grade **1 may
also be used as an alternative to **4 if heavy section welding is
required and post-weld heat treatment is not possible.
Machining
A "Ugima" improved machinability version of grade **4 is
available in bar products. "Ugima" machines significantly better
than standard **4 or **4L, giving higher machining rates and
lower tool wear in many operations.
Dual Certification
It is common for **4 and **4L to be stocked in "Dual Certified"
form, particularly in plate and pipe. These items have chemical
and mechanical properties complying with both **4 and **4L
specifications. Such dual certified product does not meet **4H
specifications and may be unacceptable for high temperature
applications.
Applications
Typical applications include:
• Food processing equipment, particularly in beer brewing, milk
processing & wine making.
• Kitchen benches, sinks, troughs, equipment and appliances
• Architectural panelling, railings & trim
• Chemical containers, including for transport
• Heat Exchangers
• Woven or welded screens for mining, quarrying & water
filtration
• Threaded fasteners
• Springs
zjhua***9 (at) msn(doc)cn
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| País: |
China |
| N º de Modelo: |
KA20630460E20
|
| Precio FOB: |
2800 ~ 3500 / Metric Ton (Negociable)
Obtener el precio más reciente
|
| Lugar de origen: |
CHINA |
| Precio de pedido mínimo: |
2800 per Metric Ton |
| Cantidad de pedido mínimo: |
25 Metric Ton |
| Detalle de embalaje: |
export standard as picture |
| El tiempo de entrega: |
PROMPT |
| Capacidad de suministro: |
6000 Metric Ton per Month |
| Tipo de pago: |
T/T, L/C |
| Grupo de productos : |
- |
