Unlock instant, AI-driven research and patent intelligence for your innovation.

Valve seat made of iron-based sintered alloy

a technology of sintered alloy and valve seat, which is applied in the direction of engine components, machines/engines, mechanical apparatus, etc., can solve the problems of insufficient wear resistance, low strength, and strong shock, and achieve high wear resistance, low emission, and improved fuel efficiency

Inactive Publication Date: 2013-11-07
RIKEN CO LTD
View PDF3 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The invention provides a valve seat made of an iron-based sintered alloy with high wear resistance in a wide temperature range. This allows it to be used in direct injection engines with improved fuel efficiency, low emission, and high power. By controlling the amount of solid lubricants and dispersing different types of hard particles, the valve seat has high strength and self-lubrication, as well as excellent wear resistance even without lubrication.

Problems solved by technology

Valve seats used with intake valves and exhaust valves for keeping the gas tightness of combustion chambers are exposed to combustion pressure, and receive strong shock repeatedly by the reciprocating motion of valves.
However, valve seats of conventional iron-based sintered alloys, in which calcium fluoride as a solid lubricant is dispersed in a large amount in a matrix, have low strength, as well as insufficient wear resistance in a low temperature range, so that they are not suitable for use in a wide temperature range.
Also, valve seats of conventional iron-based sintered alloys containing only ferromolybdenum as hard particles have insufficient wear resistance in a wide temperature range.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Valve seat made of iron-based sintered alloy
  • Valve seat made of iron-based sintered alloy
  • Valve seat made of iron-based sintered alloy

Examples

Experimental program
Comparison scheme
Effect test

examples 1-5 (

E1-E5) and Comparative Examples 1-6 (C1-C6)

[0023]Pure iron powder, and / or prealloy powder comprising 2.5% of Mo, 1% of Si, and 0.02% of C, the balance being iron and inevitable impurities, each of which had a particle size distribution with a peak in 150-200 mesh, were mixed with Mo powder, Si powder, Ni powder and graphite powder in such amounts as to provide the composition of Matrix A-K shown in Table 1, and with the first hard particles L-R of Fe-Mo-Si alloys shown in Table 2, the second hard particles S-Y of Fe-C-Cr-Mo-V alloys shown in Table 3, and the solid lubricant powder shown in Table 4, at ratios (% by mass) shown in Table 4, and blended by a blender to prepare each powder mixture.

TABLE 1Matrix (Fe—C—Si—Mo—Ni Alloy)No.CSiMoNiFeA2.51.50.51.0BalanceB*1.22.02.52.0BalanceC*1.51.05.05.0BalanceD1.10.42.51.0BalanceE*1.31.02.53.0BalanceF1.30.52.53.0BalanceG*1.10.55.02.0BalanceH0.91.00.51.0BalanceI0.80.52.54.0BalanceJ1.52.2—2.0BalanceK*2.01.02.5—BalanceNote:*Prealloy powder was u...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Fractionaaaaaaaaaa
Fractionaaaaaaaaaa
Fractionaaaaaaaaaa
Login to View More

Abstract

A valve seat of an iron-based sintered alloy having high wear resistance in a wide temperature range, which can be used in direct injection engines with improved fuel efficiency, low emission and high power, is obtained by limiting the amount of a solid lubricant dispersed in the matrix of the valve seat of an iron-based sintered alloy, and dispersing at least two types of hard particles having different hardnesses in the matrix, thereby providing high strength and self-lubrication, as well as improved wear resistance under no lubrication in a wide temperature range.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a valve seat for internal combustion engines, particularly to a valve seat made of an iron-based sintered alloy, which is used under the condition of low lubrication by fuel injection into cylinders.BACKGROUND OF THE INVENTION[0002]For environmental protection, improved fuel efficiency, lower emission and higher power are increasingly needed to internal combustion engines, and high-load combustion and high-load engine specifications require combustion chamber parts to have higher wear resistance in a wide use temperature range. Valve seats used with intake valves and exhaust valves for keeping the gas tightness of combustion chambers are exposed to combustion pressure, and receive strong shock repeatedly by the reciprocating motion of valves. In addition, because valves are not only reciprocatable but also rotatable around their stems, sliding surfaces of valve seats which come into contact with valves are required to have...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): F01L3/02
CPCF01L3/02C22C27/04F01L1/0532F01L1/143F01L2800/18F01L2810/02F01L2820/01B22F5/008C22C33/0207C22C33/0221C22C33/0228C22C38/02C22C38/08C22C38/12C22C38/22C22C38/24F01L2303/00
Inventor TAKAHASHI, RINTAROUHENMI, HIROJISHIKANAI, SYUUICHI
Owner RIKEN CO LTD