430F Stainless steel 1.4104 (NOUS 43020)

What is stainless steel 430F (NOUS 43020)1.4104?

1.4104 stainless steel is a martensitic stainless steel grade which can be heat threated. This grade is written as 1.4104 or X14CrMoS17 according to EN norm and it is written as UNS S43020 according to UNS norm. 1.4104 material is commenly mixed up with 430F grade stainless steel. There is only a small carbon percantage difference between 430F and 1.4104 grade and the main difference is that 1.4104 grade can be heat threated, but 1.4105 (430F) can not be heat threated. Because of this similarity, most of the people know this grade as 430F (1.4104), but this is a mistake. 1.4104 grade does not have any equivalent in AISI norm. (Like 304 or 316 or 430F) So this is the biggest reason wht 430F and 1.4104 is commenly mixed. 1.4104 grade includes good amouth of sulfur and this sulfur makes the machinability of this grade easy. The carbon content level is good enough for heat threatment and 1.4104 grade materials can be heat threated. 1.4104 material usually used in pump parts and automative parts. Since 1.4105 (AISI 430F) et 1.4104 grade are really similar, in many applications both of these stainless grades can be used alternative to each other.

Equivalent Grades of Stainless Steel 1.4104

W.Nr. 1.4104	BS	SIS 2383
AISI 430F	AFNOR Z13CF17	JIS 430F
X14CrMoS17	DIN 17740 1.4104

1.4104 Chemical Composition

C %	Et %	Mn %	P. %	S %	Cr %	Mo %
0,10 – 0,17	maximum 1,00	maximum 1,50	maximum 0,040	0,150 – 0,350	15,50 – 17,50	0,20 – 0,60

Propriétés mécaniques 

The values given refer to the heat treatment condition +QT650 in the diameter range ≤ 60 (Ø in mm) et 60 < d ≤ 160 (Ø in mm) at room temperature (according to EN 10088-3).

Hardness in HB: ≤ 220

Yield strength Rp0.2 in Mpa: ≥ 500

Strength / tensile strength Rm in Mpa: 650-680

Elongation at break A in % (longitudinal) at ≤ 60: ≥ 12

Elongation at fracture A in % (longitudinal) at 60 < d ≤ 160: ≥ 10

Propriétés physiques

Density in kg/dm3	7,7
Electrical resistance at 20°C in (Ω mm2)/m	0,7
Thermal conductivity at 20°C in W/(m K)	25
Specific heat capacity at 20°C in J/(kg K)	460

Supplied Forms

• Round bars
• Square bars
• Hexagonal bars
• Flat bars
• Seamless and welded pipes
• Hot and cold rolled plates and sheets
• Forged bars and flanges

Corrosion Resistance

Due to the high sulfur content, the corrosion resistance is impaired.

Forging

As a result of the high sulphur content and mixed ferrite-austenite structure that exists at

the forging temperatures, care should be taken when forging 1.4104. When forging is to be

performed, gradual heating to a temperature of about 850 °C is recommended prior to more

rapid heating to a temperature of between 1100 °C and 1130 °C. Forging then takes place

between 1130 °C – 1050°C.

Traitement thermique

	Temperature in °C	Cooling
Hot forming	1.100 – 800	air
Traitement thermique
Soft annealing (+ UN)	750 – 850	furnace, air
Tempering (+ QT)
Hardening	950°C – 1.070°C	polymer, oil, air
Tempering (+ QT650)	550°C – 650°C	air

Cold forming:

Cold forming is possible.

Welding

The material AISI 430F (1.4104 / X14CrMoS17) has poor welding properties. This material is therefore not usually used for welding. This martensitic steel is not suitable for common welding processes such as TIG welding, arc welding or submerged-arc welding. It can be used for resistance welding. Subsequent heat treatment is required here.

Applications

The main applications of stainless steel 1.4104 430F include:

• transmission
• Auctions
• fasteners
• Sprockets