Alloy МНМц68-4-2

Designation

Name The value
Designation GOST Cyrillic МНМц68-4-2
Designation GOST Latin MHMts68-4-2
Transliteration MNMts68-4-2
By chemical elements CuNiMn68-4-2

Description

Alloy МНМц68−4-2 is used: for the manufacture of tapes, strips and bars used for welding of machinery; for brazing of sintered hard alloys in the manufacture of carbide cutting tools.

Note

The alloy system Copper-Zinc-Nickel-Manganese.
Solder МНМц68−4-2 — single layer, good flow on the brazed surfaces, in comparison with solder ЛМцЖ57−1,5−0,75 provides higher strength of the solder joint, but causes a higher level of residual stress in soldering the solid alloy, which may increase the likelihood of cracking during production and damage when operating the tool. Recommended for brazing of cutting tools operating under severe conditions at elevated temperatures. The application is only useful if the strength of the solder joint when using solder ЛМцЖ57−1,5−0,75 insufficient.

Standards

Name Code Standards
Non-ferrous metals, including rare, and their alloys В51 GOST 28873-90, OST 48-184-81

Chemical composition

Standard Mn Ni Cu Zn
OST 48-184-81 1.5-2.5 4-5 62-68 Rest
Cu is the basis.
According to OST 48-184-81, the total content of all impurities in the alloy MNMc68-4-2 should be ≤ 0.30%.

Mechanical properties

sT|s0,2, MPa σU, MPa d y, % KCU, kJ/m2
Solder supplied at OST 48-184-81
≥137 ≥323 ≥43 ≥42 ≥1270
≥108 ≥255 ≥47 ≥45 ≥1160
≥98 ≥235 ≥40 ≥35 ≥930
≥98 ≥206 ≥30 ≥25 ≥740
≥98 ≥157 ≥15 ≥15 ≥590
≥69 ≥98 ≥12 ≥25 ≥350
≥39 ≥49 ≥23 ≥25 ≥460

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d Elongation after rupture
y The relative narrowing
KCU Toughness