Aluminium Welding Alloy 4145

Technical Data Sheet


Chemical Composition Limits
Weight% Al Si Cu Fe Zn Cr Mn Mg Others Others
Alloy 4145 Bal 9.3-10.7 3.3-4.7 0.80 max 0.20 max 0.15 max 0.15 max 0.15 max 0.05 max each 0.15 max each

Alloy 4145 was originally developed as a brazing alloy due to its low melting temperature and high fluidity. Alloy 4145 provides very low susceptibility to weld cracking when used with 2xxx series alloys or Aluminium-Copper or Aluminium-Copper-Silicon castings. Alloy 4145 is often preferred over Alloy 2319 when MIG Welding as it "Wets" out better and has a brighter looking weld, however Alloy 4145 does have a lower weld tensile strength than Alloy 2319.

Used on

Joining grades 201, 206, 224, 314, 330, 354, 355 to 6005, 6061, 6063, 6101, 6151, 6201, 6351, 6009, 6010, 6070. C355 A356, 357, 413, to 201, 206, 224, 319, 330, 354, 355, C355. LM4, LM16, LM20, LM25, LM99 to 6000 series as above and cast alloy combinations as shown. 2014, 2024.
Repair of 2xxx wrought alloys and Al-Cu, Al-Si-Cu casting alloys.

Cross-Reference of Specifications ALCUBRAZE
MSRR 9500/35
716 AL
AMS 4184D Filler Metal, Aluminium Brazing
ALLOY 4145
UNS A 94145
FED-QQ-B-655, Class FS-BAl Si-3
Availability Ex stock MIG spools and TIG rods

For all stock availability contact Sales.

Weld Properties

Melting range 968° - 1085°F, Density 2.74gm/cc
ALLOY 4145 is an Al-Si-Cu welding alloy with low melting range which enables successful repair welds to be made in copper containing heat treatable Al-alloys.

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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.