Heat-resistant austenitic stainless steel and a production process thereof

Inactive Publication Date: 2005-09-08
DAIDO STEEL CO LTD
View PDF1 Cites 73 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0015] An object of the invention is to overcome the problems described above and to provide a heat-resistant austenitic stainless steel having high-temperatur

Problems solved by technology

Among the above-described various metal materials, the conventional austenitic stainless steel and the precipitation hardened stainless steel are relatively low in cost; however, the working temperatures thereof ar

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

Examples

Experimental program
Comparison scheme
Effect test

Example

[0081] Further, the same tests were conducted on SUH660 (Comparative Example 1) as a currently-used typical material. A production process of SUH660 before cold working was the same as that of Examples 1 to 14. Further, the cold working was conducted at a cold working ratio of 50%, and SUH660 was formed into a round bar of 17 mm in diameter. Furthermore, for aging treatment, the bar was air-cooled after kept at 720° C. for 4 hours.

Example

[0082] Furthermore, the same tests were conducted on a low-Mo material (Comparative Example 2), a high-Mo material (Comparative Example 3), a low-Cr, low-N and low-PN material (Comparative Example 4), a high-Cr material (Comparative Example 5), a low-Ni material (Comparative Example 6), a high-Ni material (Comparative Example 7), a high-Al material (Comparative Example 8), and a high-Mn material (Comparative Example 9). Production process of Comparative Examples 2 to 9 was the same as that of Examples 1 to 14.

[0083] Table 1 shows alloy composition of the respective materials. Further, Table 2 shows primary hardness (HRC) after the aging treatment, tensile strength (MPa) at 600° C. and 700° C., hardness (HRC) after kept at 600° C. and 700° C. for 400 hours, and the residual stress ratio (%). As demonstrated in Tables 1 and 2, Examples 1 to 14 respectively satisfy requirements for both the primary hardness of not less than 45 HRC and the residual stress ratio at 700° C. of not less t...

Example

Comparative Example 3: High Mo

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
Temperatureaaaaaaaaaa
Temperatureaaaaaaaaaa
Temperatureaaaaaaaaaa
Login to view more

Abstract

To provide a heat-resistant austenitic stainless steel having high-temperature strength and sag-resistance capable of resisting working temperatures of not less than 550° C. as well as being low in cost, and a production process thereof. The steel consistent with the present invention contains not more than 0.1 wt % C, less than 1.0 wt % Si, 1.0 wt % to 10.0 wt % Mn, not more than 0.03 wt % P, not more than 0.01 wt % S, 0.01 wt % to 3.0 wt % Cu, 7.0 wt % to 15.0 wt % Ni, 15.0 wt % to 25.0 wt % Cr, 0.5 wt % to 5.0 wt % Mo, not more than 0.03 wt % Al, 0.4 wt % to 0.8 wt % N, and the remainder substantially consisting of Fe and unavoidable impurities.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a heat-resistant austenitic stainless steel and a production process thereof, more specifically relates to a heat-resistant austenitic stainless steel suitable for a steel material for heat-resistant members used in exhaust systems of an automobile engine and an aeroengine, industrial manufacturing facilities and the like, and a production process thereof. [0003] 2. Description of Related Art [0004] Conventionally, for heat-resistant members used in exhaust systems of an automobile engine and an aeroengine, industrial manufacturing facilities and the like, high-temperature strength and sag-resistance are required, and various metal materials are selectively used according to working temperatures. For example, in a relatively low-temperature range of not more than 350° C., an austenitic stainless steel (e.g., SUS304 and SUS316), a precipitation hardened stainless steel (e.g., SUS631J1...

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): C21D8/06C21D6/00C22C38/00C22C38/42C22C38/44C22C38/58
CPCC22C38/001C22C38/44C22C38/42
Inventor HAMANO, SHUJISHIMIZU, TETSUYA
Owner DAIDO STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products