Casting alloys of aluminum-tin

These aluminum alloys, doped tin, specially developed for bearings. Quality bearings main criteria are the load-bearing capacity, fatigue and corrosion resistance in lubrication conditions in internal combustion engines. Aluminum Alloy Bearings, tin alloyed, unsurpassed among other types of bearing materials.

Aluminum tin phase diagram

Aluminum tin phase diagram

Aluminum-tin alloys contain about tin 6 %, as well as small amounts of copper and nickel to increase strength. They are used for cast bearings.. It is tin that provides very good glide in these alloys..

American aluminum-tin alloys

American Tin Aluminum Alloys 850.0, 850.1 and 852.0 can be cast as in sand, so in the chill mold. However alloys 850.0 (6,3Sn-1Cu-1Ni) и 852.0 (6,3Sn-2Cu-1,2Ni-0,8Mg)обычно льют только в постоянные формы. Sand casting is used for large rolling mill bearings, which are usually made of alloy 851.0 (6,3Sn-2,5Si-1Cu-0,5Ni).

Bearing structure

The “bearing” properties of aluminum-tin alloys are highly dependent on the casting method. Finely dispersed tin distribution is essential for optimum bearing properties.. This requires a small interdendritic distance., and such a distance can only be obtained with fast cooling casting methods.

Long cure interval

In terms of the casting process, the aluminum-tin alloy system is unique. The solidification of the alloy in the mold begins at a temperature of about 650 oC, and the tin remains liquid somewhere up to the temperature 225 oC. Such a too large temperature hardening range presents difficulties for casting. High solidification rates of castings are recommended to avoid excessive macrosegregation..

A casting aluminum alloy 850.0

Формула сплава:


Химический состав:

  • copper: 0,7-1,3 %;
  • magnesium: 0,10 макс.;
  • кремний: 0,7 % макс.;
  • iron: 0,7 % Max.
  • lead: 5,5-7,0 %;
  • nickel: 0,7-1,3 %;
  • titanium: 0,20 % макс.;
  • другие: 0,30 % макс.;
  • алюминий: остальное.

Влияние содержания примесей:

  • high iron content, марганца или магния снижает пластичность и повышает твердость;
  • high silicon improves slip characteristics.

Типичные механические свойства в состоянии Т5:

  • прочность на растяжение: 160 MPa;
  • предел текучести: 75 MPa;
  • относительное удлинение: 10 %;
  • твердость: 45 NV;
  • коэффициент Пуассона: 0,33;
  • модуль упругости: 71,0 GPa.

Физические свойства:

  • плотность: 2,880 g / cm3;
  • температура ликвидус: 650 ºS;
  • температура солидус: 225 oC.

Технологические свойства:

  • температура плавления: от 650 by 730 ºS;
  • температура разливки: от 650 by 705 ºS;
  • температура старения: 230 oC, excerpt - 8 hours.

Источник: Aluminum and Aluminum Alloys, ASM International, 1996