Materialsheet DIN 1705 Rg 7 Gunmetal

(Comp. norms: SAE 660, ISO CuSn7Pb7Zn4, CuSn7)
Main elements (nom. values)
  • Cu 81-85 %
  • Sn 6-8 %
  • Pb 5-7 %
  • Zn 3-5 %
Max. impurities:
  • Ni 2,0 % (can be part of the Cu-cont.)
  • Mn 0,2 %
  • P 0,05 %
  • Sb 0,2 %
  • S 0,1 %
  • Övr. 0,1 %
Mekaniska egenskaper

Sträckgräns (Rp N/mm 2 ): 120-150 N/mm 2
Brottgräns (Rm N/mm 2) ):
270-330 N/mm 2
Förlängning i % A 5 :
16-26 %
Hårdhet/Brinell:
70-85 HB
(Alla värden = Nominella värden)

Mechanical properties

Yield stress (Rp N/mm 2 ): 120-150 N/mm 2
Tensile strength (Rm N/mm 2 ): 270-330 N/mm 2
Elongation in %, A 5 : 16-26 %
Hardness/Brinell: 70-85 HB

Density ~ 8,8

Mating material: Min. surface hardness 165 HB Rec. surface roughness < 1 Ra.

Other information

Rg7 is not suited for welding. Soldering (hard-soldering) is not to recommend (due to its lead-content), but is possible. It is possible to glue. Easy to machine. Few sensitive to edge pressure.

Examples on areas of use

All sorts of bearings and sliding elements for general applications and medium stress. Saltwater resistant.

Guidelines for turning, drilling and milling of Rg 7 ( R ot g uß 7) Gunmetal

(normal working conditions is presumed)

 

Work operations   Surface
roughness
Nose radius
mm
Cutting Speed
m/min
Feeding
mm/revs
Hµm Raµm
Turning Hard metal
Qual. H20
16
4
4
1
0,4
0,8
285-360 0,15
0,08
Drilling Ø 2-60mm High speed
Boring tool
      70 0,08-0,40
Milling Ø 63 mm 6 cuts Hard metal
Qual. H20
16
4
4
1
  Rpm
1200
mm/min
800
550
Milling Ø 100 mm 8 cuts Hard metal
Qual. H20
16
4
4
1
  1000 1000

675

Milling Ø 160 mm 12 cuts Hard metal
Qual. H20
16
4
4
1
  650 1100
700
Milling Ø 200 mm 14 cuts Hard metal
Qual. H20
16
4
4
1
  500 850
550

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