Iron material for high-temperature-resistant bearing bushings, bearing bushing made of said material, and turbocharger having such a bearing bushing

Patent metadata

Field	Value
Publication number	US-11111819-B2
Application number	US-201716327918-A
Country	US
Kind code	B2
Filing date	Jul 31, 2017
Priority date	Aug 24, 2016
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

Bearing bushings which are exposed to highly elevated temperatures during operation, corresponding high-temperature-resistant bearing bushings and exhaust-gas turbochargers having at least one such bearing bushing, include an iron material having a material composition which, apart from iron, has at least carbon, silicon, manganese, nickel, chromium, molybdenum and tungsten alloy constituents in certain amounts. This material composition ensures sufficient temperature resistance and self-lubricating properties with simultaneously good machining properties and a moderate price.

First claim

The invention claimed is:

1. An iron material, comprising:
a material composition including iron, Fe and at least alloy constituents within limit amounts stated below in percent by weight, wt. %:
carbon, C: 1.5 to 3.0 wt. %;
silicon, Si: 1.0 to 6.0 wt. %;
manganese, Mn: 1.5 to 7.00 wt. %;
nickel, Ni: 12.0 to 36.0 wt. %;
chromium, Cr: 6.0 to 12.00 wt. %;
phosphorus, P: 0.05 to 0.25 wt. %;
copper, Cu: 0.5 to 7.5 wt. %;
molybdenum, Mo: 2.0 to 5.0 wt. %; and
tungsten, W: 0.8 to 2.0 wt. %,
wherein the carbon constituent comprises free carbon incorporated into a structure of the iron material composition as lamellar graphite, nodular graphite, or vermicular graphite to improve self-lubrication properties of the iron material.

2. The iron material according to claim 1 , wherein said material composition forms a high-temperature-resistant bearing bushing.

3. A bearing bushing for use under high-temperature conditions, the bearing bushing comprising or being manufactured from the iron material according to claim 1 .

4. An exhaust-gas turbocharger, comprising:
an exhaust-gas turbine;
a fresh-air compressor;
a bearing unit;
at least one movable actuating apparatus for influencing fluid mass flows flowing through at least one of said exhaust-gas turbine or said fresh-air compressor; and
at least one bearing bushing for use under high-temperature conditions, said at least one bearing bushing movably mounting said actuating apparatus, and said at least one bearing bushing including or being manufactured from the iron material according to claim 1 .

5. The exhaust-gas turbocharger according to claim 4 , wherein said at least one actuating apparatus is a wastegate valve, an overrun air recirculation valve or an adjustable turbine geometry.

Assignees

• Cpt Group Gmbh

Inventors

• Thomas Martin
• Muench Guenter
• Waas Alexander

Classifications

• C22C37/04

  containing spheroidal graphite · CPC title

• C22C37/08

  with nickel · CPC title

• C22C37/10

  containing aluminium or silicon · CPC title

• F16C17/10

  for both radial and axial load · CPC title

• F16C2204/60

  Ferrous alloys, e.g. steel alloys · CPC title