DAIKOWS 420B

SAW
  • FERRITIC - MARTENSITIC STAINLESS STEEL
420

Description

Martensitic harfacing wire rod for 13%Cr stainless steels
This wire rod deposits a weld metal similar to 410 with higher chromium and carbon contents and is used for surfacing operation requiring corrosion resistance and wear resistance on matching base materials and also on CMn steels. Application include welding of similar parental metal, weld overlay and thermal spraying. Suitable for cladding of continuous casting rolls.
Specifications
ISO 14343-B
SS420
AWS A5.9
ER420
Shielding
DAIKOFLUX 493-W
Positions
PA, PB, PC
Current
DC/AC
Packaging Type
K415 spool and drums.
Asme qualifications
F-No (QW432)
6
A-No (QW442)
6

Pren

13

Hardness

40HRC - 50HRC PWHT
Chem. Comp. %
DEFAULT
C
0.3
Mn
0.6
Ni
0.5
Cr
13
P
0.03
S
0.03
Si
0.5
Cu
0.3
Mechanical Properties
min
variant
Tensile strength Rm MPa
450
750
Yield strength Rp0.2 MPa
250
500
Elongation A (L0=5d0) %
15
30
Impact Charpy ISO-V
-
50J @ 20°C
Impact Charpy ISO-V
-
-
Welding Parameters
2.4 mm
Ampere
250A - 420A
Voltage
28V - 32V
Packaging
Ø 2,0÷4,0mm
Packaging Type
K415 spool and drums.
Anti-wear Characteristics
Adhesive wear
Abrasive wear
Impact
Corrosion
Heat
420
Description

Application

Sharing similarities with ER410, this alloy distinguishes itself through a slight increase in both chromium and carbon contents. Its utilization extends to a myriad of surfacing operations where a combination of corrosion resistance (attributed to its 12 percent chromium composition) and augmented hardness for heightened wear resistance is paramount. This alloy finds its primary application in surfacing the sealing faces of valves employed in gas, water, and steam piping systems, especially under service temperatures reaching up to +450 °C. Beyond this, its versatility encompasses various applications, including welding similar parental metal, weld overlay, thermal spraying, and the cladding of continuous casting rolls. Remarkably, if the envisaged application demands the use of parts in the "as-welded" condition, achieving a ductile joint is entirely feasible. This is achieved through the application of austenitic fillers, with options such as 22 12 L/309, 18 8 Mn/307, or 25 20/310 proving suitable for this purpose.

Alloy Type

Ferritic martensitic stainless steels.

Microstructure

The microstructure comprises tempered martensite and some carbide.

Materials

Corrosion resistant Cr-steels as well as other similar-alloyed steels with C-contents ≤ 0.30 % (repair welding), heat resistant Cr-steels of similar chemical composition.
EN W.Nr.: 1.4006 (X12Cr13), 1.4021 (X20Cr13), +
ASTM: 410, 420.

Welding & PWHT

Implementing pre-heating and meticulous interpass temperature control during welding, coupled with a deliberate and gradual cooling process followed by Post Weld Heat Treatment (PWHT), serves as effective preventive measures against cracking. For joint welding, a recommended preheating temperature of +200 – 300 °C is advisable, the specific value depending on the alloy type and strength levels. Correspondingly, the interpass temperature should be maintained within the same range. Ensuring an optimal heat input is crucial, avoiding extremes with a recommended range of 0.5 – 1.5 kJ/mm. The hardness of the deposit is contingent upon the degree of dilution with the base metal and its chemical composition. Generally observed is the correlation where higher degrees of dilution and higher C-content in the base metal result in increased deposit hardness. Post-weld heat treatment becomes a requisite to reinstate ductility to the weld zone. This involves tempering at temperatures ranging from +700 – 750 °C, a process aimed at enhancing the toughness of the welded structure. This comprehensive approach guarantees the mechanical integrity and performance of the welded joints.

DO YOU NEED HELP?

Go to our dedicated section or contact us
Contact us
Daiko supporting the environment
Questo sito si avvale di cookie necessari al suo funzionamento ed utili alle finalità illustrate nella cookie policy.

Carrello

Il carrello è vuoto