valve steel


Typical Analysis :

Carbon 0.48/0.58% Manganese 8.0/10.0% Silicon 0.25% max
Chromium 20.0/23.0% Phosphorus 0.050% max Sulfur 0.035% max
Nitrogen 0.38/0.55% Iron Balance Nickel 3.25/4.50%

Applications :
This alloy has been used primarily in exhaust valves and the head portion of two piece valves.

Workability :
Forging : 21-4 N can be readily forged by both upset and extrusion methods at temperatures in the range of 2050 / 2150 °F (1121 / 1177 °C). Do not forge above 2200 °F (1204 °C) or below 1800 °F (982 °C). Forgings can be rapidly cooled.

Heat Treatment :
Solution Heat Treatment : Heat approximately for 1 hour at 2125 °F (1163 °C), and cool rapidly.

Solution Treated and Aged : Heat to 2125 °F (1163 °C), hold for 1 hour followed by water quench. After complete cooling, heat to 1400 °F (760 °C), hold for 16 hours followed by air cooling.

Typical Mechanical Properties :
Heat Treatment : 2150 F (1177C) / 1hr / WQ + 1400 F (760 C) / 16hr / AC

Test Temperature 0.2% Yield Strength Ultimate Tensile Strength % Elongation % Reduction Of Area Hardness
°F °C Ksi MPa Ksi Mpa
Room Room 100.7 694 168.0 1158 10.7 10.8 37 HRC
1400 760 44.9 310 63.9 441 31.2 39.3 77 HRB

Hot Tensile Impact Test :
Heat Treatment : 2150 degree F (1177 degree C) / 1hr / WQ + 1400 degree F (760 degree C) / 16hr / AC

Test Temperature % Impact Strength % Impact Elongation % Impact Reduction of Area
°F °C Ft-Ib
1940 1060 117 49.6 71.0
2100 1149 98 50.5 72.7

Creep Test Data :
1350 degree F (732 degree C). Heat Treatment : 2150 degree F (1177 degree C) / 1hr / WQ + 1400 degree F (760 degree C) / 16hrs/ AC

Stress ASTM Grain
Size
Time for the Indicated Total Deformation (hrs.) Calculated Stress to Produce 1% Creep in 100 hrs.
Ksi Mpa 0.5% 1.0% Ksi Mpa
25 172.0 4 3.5 20.0 18 124
20 138.0 4 4.5 25.0
10 689.0 4 450.0 1850.0

Brinell Hardness vs. Temperature :
Heat treatment : 2150 degree F (1177 degree C) / 1hr. / WQ + 1400 degree F (760degree C) /16hrs. / AC

 

Typical Analysis :
Carbon 0.45% Manganese 0.50% Silicon 3.25% Chromium 8.50%
Applications :
This alloy offers good resistance to oxidation and corrosion by combustion products of gasoline engines where the operating temperature is below 1000 °F (538 °C). It has been widely used for intake valves and exhaust valve stems in internal combustion engines.
Workability :
Forging : X45CrSi93 (SIL No. 1) can be readily forged by both upset and extrusion methods at temperatures in the range of 1900 / 2100 °F (1038 / 1149 °C). Forgings should be slow cooled from forging heat.
Machinability : Machinability  properties are comparable to the standard 18-8 stainless alloys but more difficult than SAE 3140.
Heat Treatment :
Full Anneal : Heat to 1400 / 1450 °F (760 / 788 °C), and air or water quench. This will result in a hardness of 27 / 29 Rockwell C.
Hardening : Heat to 1850 / 1925 °F (1010 / 1052 °C) and oil quench. Rockwell hardness C 60 / 62.
Tempering Temperature Rockwell C Hardness
°F °C
600 316 58
800 427 58
900 482 57
1000 538 53
1100 593 43
1200 649 37
1300 704 34
Typical Mechanical Properties :
Temperature Mechanical Properties
Specimen treated 1450 °F (788 °C), water quenched
Test Temperature 0.2% Yield Strength Ultimate Tensile Strength % Elongation in 4 D % Reduction Of Area Brinell Hardness V-Notch Charpy Impact
°F °C Ksi Mpa Ksi Mpa Ft-Ib J
77 25 82.5 569 133.0 917 22.5 49.0 269 2 2.9
1000 538 53.0 365 67.5 465 40.5 71.0 125 60 81.3
1100 593 29.5 203 43.5 300 38.0 85.0 85 75 101.9
1200 649 15.0 103 31.0 214 73.5 92.5 45 95 128.4

Typical Analysis :
Grade Carbon Silicon Manganese Chromium Molybdenum Nickel
SUH 3 0.4% 2.15% 0.6% max 11.0% 1.0% 0.6% max
SUH 11 0.5% 1.5% 0.6% max 8.5% 0.6% max
Applications :
The alloys offer very good resistance to heat.Bars used in quenched and tempered condition for good combination of impact and mechanical properties for demanding applications like- Automotive Valves.
Typical Mechanical Properties of quenched and Tempered bars 25mm max dia :
Grade Proof Stress n/mm2 UTS n/mm2 El% RA% Charpy J/cm2 BHN
SUH3 685 930 15 35 20 269
SUH11 685 880 15 35 20 262
Hardness BHN annealed bars:
SUH3 269 max
SUH11 269 max
Heat-treatment :
Grade Annealing Quenching Tempering
SUH3 800-900 °C Slow cooling 980-1080 °C Oil quench 700-800 °C Rapid cooling
SUH11 750-850 °C Slow cooling 1000-1050 °C Oil quench 650-750 °C Rapid cooling