Aluminium Welding Alloy 4043

Technical Data Sheet


Chemical Composition Limits
Weight% Al Si Fe Cu Ti Zn Mn Mg Others Others
Alloy 4043 Bal 4.5-6.0 0.60 max 0.30 max 0.15 max 0.10 max 0.15 max 0.20 max 0.05 max each 0.15 max total

Alloy 4043 is one of the oldest and most widely used welding and brazing alloys. AL4043 can be classed as a general purpose type filler alloy. Due to the addition to silicon alloy 4043 results in improved fluidity (wetting action) to make alloy 4043 the preferred choice by welders. Alloy 4043 is less sensitive to weld cracking and brighter and almost smut free welds.

Aluminium MIG and TIG Welding wire and Rods

Used on 1xxx, 3xxx, 6xxx series alloys.
2014, 2219, 5005, 5050, 5052, 7005, 7039, N21.
Al-Si, Al-Si-Mg casting alloys and combinations of above materials.
Al - Lithium alloys.
DTD372B, LM4, LM2, LM6, LM9, LM20, LM25, LM2 .
Cross-Reference of Specifications MSRR 9500/32
AMS 4190D Aluminium Alloy, Welding Wire
N21 (NG21)
MSRR 8065
UNS A 9 4043
Fed-QQ-R-556 Class 4043
Alloy 4043 A (BS 2901 PT4)
ER4043, R4043 (AWS A5.10.92)
Availability Ex stock MIG spools and TIG rods Spools 0.5kg, 2.5kg and 15kg European manufacture
Spools 1 lb, 5 lb and 25 lb American manufacture
Rods 1 kg, 2.5kg, 5kg and 10kg packs European manuf.
1000mm lengths, Flag tagged for traceability
Rods 5 lb American manufacture
Flag tagged for traceability
For all stock availability contact Sales.

Weld Properties
Melting range 573°- 625°C
Density 2.68gm/cc
ALLOY 4043 is an Al-5% Si alloy, non-heat treatable.
ALLOY 4043 has a lower melting range than the base metals for which it is commonly used and relieves contraction during weld cooling.

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Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.