EP0305746B1 - Verfahren zur Herstellung von mechanischen Teilen mit verschleiss- und/oder korrosionsfester Beschichtung - Google Patents

Verfahren zur Herstellung von mechanischen Teilen mit verschleiss- und/oder korrosionsfester Beschichtung Download PDF

Info

Publication number
EP0305746B1
EP0305746B1 EP88112432A EP88112432A EP0305746B1 EP 0305746 B1 EP0305746 B1 EP 0305746B1 EP 88112432 A EP88112432 A EP 88112432A EP 88112432 A EP88112432 A EP 88112432A EP 0305746 B1 EP0305746 B1 EP 0305746B1
Authority
EP
European Patent Office
Prior art keywords
coating
corrosion
wear
sintering
production
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP88112432A
Other languages
English (en)
French (fr)
Other versions
EP0305746A1 (de
Inventor
Sante Quaranta
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Iveco SpA
Original Assignee
Iveco Fiat SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Iveco Fiat SpA filed Critical Iveco Fiat SpA
Publication of EP0305746A1 publication Critical patent/EP0305746A1/de
Application granted granted Critical
Publication of EP0305746B1 publication Critical patent/EP0305746B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/18—After-treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
    • B22F3/1208—Containers or coating used therefor
    • B22F3/1258—Container manufacturing
    • B22F3/1266—Container manufacturing by coating or sealing the surface of the preformed article, e.g. by melting

Definitions

  • the present invention relates to a method for the production of components having a wear- and/or corrosion-resistant coating.
  • the present invention relates to a method for the coating of products required to withstand high hammering, rolling and frictional stresses with or without corrosion due to external agents, both cold and hot, with materials which have high wear resistance.
  • products for example, tappets, cams, eccentrics, dies, etc.
  • tappets, cams, eccentrics, dies, etc. are normally constituted by a metal body which is not particularly resistant to wear and/or corrosion, in which the most stressed portion is covered with a coating of more expensive material selected in dependence on the type of stress and/or corrosive environment to which the product in question will be subject.
  • the coating of the metal substrates with friction- and/or corrosion-resistant materials is carried out hot, for example, by the techniques of deferred-arc plasma, laser-beam melting bond, spray coating by means of plasma, etc.
  • the material of the coating is stressed by considerable residual internal tensile forces as it cools and these persist in the finished product. These forces arise since the substrate, through the forces due to the adhesion between the substrate and the coating material, prevents the latter from shrinking freely from the temperature used for the coating to the ambient temperature.
  • JP-A-159566 describes a method for the production having a wear-and/or corrosion resistant coating on a portion thereof comprising the steps of forming the element, applying the coating to said portion of the element and subjecting the element with the coating to hot isostatic pressing.
  • the element may be a sintered compact; by the hot isostatic pressing a coating is obtained having good exfoliation resistance with reduced porosity and increased density.
  • the object of the invention is to provide a method which allows to control the internal stress of the coating.
  • Such object is achieved by means of a method wherein the wear-and/or corrosion resistant coating is applied to a sintered element and then subjected to a hot thermal treatment characterised by the steps of
  • the component is subjected to a pre-sintering treatment before the application of the coating.
  • a green is indicated 10 and, after the sintering process, is intended to constitute a tappet element of an internal combustion engine, comprising a shaft 11 and a flat 13 provided with a working surface 12.
  • the green 10 may, for example, be made of sintered low-alloy steel corresponding, for example, to a conventional C10.
  • a pre-sintering furnace (not illustrated), both in order to obtain a more easily handled product and in order to be able to control the dimensional shrinkage, shown in the drawings by broken lines R.
  • a pre-sintered part 14 which has characteristics of strength such as to enable it to proceed without problems to the subsequent stage of coating of the working surface 12 with a layer 16 of coating material having a melting point higher than the sintering temperature of the green and having high wear- and/or corrosion-resistance.
  • the layer 16 is constituted by powders deposited at high temperature by various techniques (deferred-arc plasma, laser meeting bond, plasma spray etc.).
  • the hot application of the coating 16 means that, as it bonds to the pre-sintered part 14 which is at a lower temperature, the coating is subjected during cooling to internal tensile stresses which persist after cooling.
  • the next stage involves the passage of the pre-sintered part 14, with the layer of coating 16, into a sintering furnace in which the pre-sintered part 14 is transformed, at a high temperature, and for a time from 1 to 3 hours into a sintered part 18 with a further change in dimensions.
  • This change means that the layer of coating 16 of the pre-sintered part 14 is transformed into a layer 16' in which the tensile stress condition is cancelled out or transformed into a compressive stress condition which, in the specific case of a tappet with a flat, is particularly suitable for the type of stress to which the product will be subjected in use (impact, rolling and sliding stress from the cam acting on the tappet).
  • any stress condition between the coating 16' and the sintered part 18 may be convenient to eliminate any stress condition between the coating 16' and the sintered part 18, or it may be opportune to maintain a condition of slight tensile stress so that any problems of thermal stress can be resolved without disadvantages to the part.
  • This "piloting" of the stress condition of the coating layer 16' may be obtained by a suitable selection of the particle size and elements of the powders used to produce the green 10, defined in dependence on the reduction in volume which is to be obtained as a result of the self-densification undergone by the product in the sintering process.
  • Another variable on which it is possible to act to produce the desired stress condition in the coating 16' is the duration of the initial pre-sintering stage.
  • the method according to the invention has advantages for the sintering of ceramic powders or metal-ceramic powder mixtures too.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Plasma & Fusion (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Powder Metallurgy (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Claims (5)

  1. Verfahren zur Herstellung von Teilen, insbesondere mechanischen Teilen, mit einer verschleiß- und/oder korrosionsfesten Beschichtung, wobei die Beschichtung auf ein gesintertes Teil aufgebracht und dann einer Hitzebehandlung unterworfen wird, gekennzeichnet durch die Schritte:
    - Formen des Teils durch Kaltverdichtung von Pulvern,
    - Vorsintern des so geformten, kaltverdichteten Teils gerade in dem Ausmaß, daß das Teil einer weiteren dimensionalen Schrumpfung als Ergebnis eines weiteren Sinterungsschrittes unterworfen werden kann, um eine vorgegebene Restspannung zu erhalten,
    - Aufbringen der Beschichtung auf das Teil, wobei die Beschichtung einen Schmelzpunkt hat, der höher als die Sintertemperatur des Teils ist, und eine Verschleiß- und/oder Korrosionsfestigkeit aufweist, die höher als diejenige des Teils ist, und
    - Aussetzen des Teils mit der Beschichtung einem drucklosen Sintervorgang, um eine dimensionale Schrumpfung des Teils und der Beschichtung zu bewirken, wodurch die inneren Rest-Zugspannungen der Beschichtungslage auf Null gebracht oder in Druck umgewandelt werden.
  2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Beschichtung mittels aussetzendem Lichtbogenplasma aufgebracht wird.
  3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Beschichtung durch Laserschmelzverbinden aufgebracht wird.
  4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Beschichtung durch Plasmaspritzbeschichten aufgebracht wird.
  5. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß das Element aus Metallpulvern hergestellt ist.
EP88112432A 1987-09-03 1988-08-01 Verfahren zur Herstellung von mechanischen Teilen mit verschleiss- und/oder korrosionsfester Beschichtung Expired - Lifetime EP0305746B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT6775487 1987-09-03
IT8767754A IT1211284B (it) 1987-09-03 1987-09-03 Procedimento per la realizzazione di pezzi meccanici dotati di un rivestimento antiusura e o anticorrosione

Publications (2)

Publication Number Publication Date
EP0305746A1 EP0305746A1 (de) 1989-03-08
EP0305746B1 true EP0305746B1 (de) 1993-10-13

Family

ID=11305030

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88112432A Expired - Lifetime EP0305746B1 (de) 1987-09-03 1988-08-01 Verfahren zur Herstellung von mechanischen Teilen mit verschleiss- und/oder korrosionsfester Beschichtung

Country Status (4)

Country Link
EP (1) EP0305746B1 (de)
DE (1) DE3884894T2 (de)
ES (1) ES2045035T3 (de)
IT (1) IT1211284B (de)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE468378B (sv) * 1990-06-11 1993-01-11 Asea Brown Boveri Saett att tillverka en kompoundkropp
WO1999023272A1 (de) * 1997-11-03 1999-05-14 Siemens Aktiengesellschaft Verfahren zur herstellung einer schutzschicht auf einem für eine heissgasbeaufschlagung ausgelegten grundkörper und ausgelegtes erzeugnis

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2620192A1 (de) * 1976-05-07 1977-11-10 Still Gmbh Schalter zum einschalten von zwei stromkreisen

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE348961C (sv) * 1971-03-15 1982-08-30 Asea Ab Forfarande for framstellning av en sintrad pulverkropp
DE2620197C3 (de) * 1976-05-07 1980-08-07 Maschinenfabrik Augsburg-Nuernberg Ag, 8000 Muenchen Verfahren zur Wärmebehandlung von Bauteilen aus hochwarmfesten Werkstoffen

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2620192A1 (de) * 1976-05-07 1977-11-10 Still Gmbh Schalter zum einschalten von zwei stromkreisen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ENCYCLOPAEDIA OF CHEMICAL TECHNOLOGY, KIRK-OTHMER, vol. 19, p. 45 *

Also Published As

Publication number Publication date
IT1211284B (it) 1989-10-12
IT8767754A0 (it) 1987-09-03
DE3884894D1 (de) 1993-11-18
EP0305746A1 (de) 1989-03-08
ES2045035T3 (es) 1994-01-16
DE3884894T2 (de) 1994-02-10

Similar Documents

Publication Publication Date Title
US4499048A (en) Method of consolidating a metallic body
CN101579740B (zh) 利用粉末冶金工艺制造钛基汽车发动机气门的方法
EP2237939B1 (de) Verfahren zur herstellung von mechanisch hochbeanspruchten teilen und insbesondere werkzeugen aus beton, durch giessen der gewünschten form und dann beschichten mit einer metallischen schicht
EP0142673B1 (de) Keramischer Verbundkörper und seine Herstellung
JPH0891951A (ja) アルミニウムと窒化ケイ素の接合体およびその製造方法
US4317850A (en) Method for applying a dense, hard, adhesive and wear-resistant layer of cermets or ceramic material on a metal object
EP0305746B1 (de) Verfahren zur Herstellung von mechanischen Teilen mit verschleiss- und/oder korrosionsfester Beschichtung
US4972898A (en) Method of forming a piston containing a cavity
KR19990045037A (ko) 질화 알루미늄-알루미늄계 복합재료 및 그 제조방법
US6470550B1 (en) Methods of making tooling to be used in high temperature casting and molding
RU2123910C1 (ru) Способ изготовления спеченных изделий
US20030106198A1 (en) Methods of making wear resistant tooling systems to be used in high temperature casting and molding
US5970306A (en) Method of manufacturing high temperature resistant shaped parts
US20030223903A1 (en) Reduced temperature and pressure powder metallurgy process for consolidating rhenium alloys
JPS646274B2 (de)
EP0399400B1 (de) Verfahren zur Herstellung gesinterter Metallprodukte sowie damit hergestellte Produkte
JPH0445458B2 (de)
JPH03291112A (ja) 圧延用ガイドローラおよびその製造方法
US7270782B2 (en) Reduced temperature and pressure powder metallurgy process for consolidating rhenium alloys
JPS6371553A (ja) ピストン式往復機械本体の構成部材及びその製造方法
JP2718777B2 (ja) 反応焼結セラミックス部材の製造方法
JP3198955B2 (ja) 金属製部品の耐酸化被膜の形成方法
JPH03240940A (ja) プラスチック成形機用スクリューおよびその製造方法
JPH03223404A (ja) プラスチック成形機用スクリューの製造方法および合金層の形成方法
SU1685607A1 (ru) Способ изготовлени составных изделий из железографитового материала

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB SE

17P Request for examination filed

Effective date: 19890722

17Q First examination report despatched

Effective date: 19901127

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB SE

REF Corresponds to:

Ref document number: 3884894

Country of ref document: DE

Date of ref document: 19931118

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2045035

Country of ref document: ES

Kind code of ref document: T3

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
EAL Se: european patent in force in sweden

Ref document number: 88112432.5

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20030630

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20030702

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20030717

Year of fee payment: 16

Ref country code: DE

Payment date: 20030717

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20030828

Year of fee payment: 16

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040801

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040802

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040802

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050301

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20040801

EUG Se: european patent has lapsed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050429

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20040802