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Heat Treatment:
440C is a high carbon chromium stainless steel providing
stainless steel properties with optimum hardness after
heat treatment. 440C can achieve a hardness of up to 60
Rockwell HRc. 440C stainless resists corrosion in normal
domestic environments and very mild industrial
enviroments, with optimum cossision resistance of 440C
achieved with a temper below about 400°C. For 440C to
achieve best cossosion resistance, surfaces must be free
of scale, lubricants, foreign particles, and coatings
applied for drawing and heading. With its high carbon
content 440C annealed stainless machines similar to a
high speed steel annealed grade
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Typical Analysis
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C.
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Mn.
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P.
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S.
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Si.
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Cr.
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Mo.
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0.95-
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1.00%
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0.04%
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0.03%
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1.00%
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16.00-
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0.75%
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1.20%
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max.
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max.
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min.
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max.
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18.00%
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max.
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Annealing
To achieve full anealing of 440B heat uniformly to 840 to 875°C.
Soak and cool very slowly in the furnace.
Hardening
To heat treat 440B heat to 1010 to 1070°C, fully soak and quench
in warm oil or cool in air. Be carefull not to overheat 440C or
full hardness will not be obtained.
Tempering
When tempering 440C a Rockwell hardness of 60HRc can be
obtained. Temper for at least one hour.
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Tempering °C
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300
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400
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500
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600
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700
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HRc
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60
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59
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57
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56
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56
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Mechanical Properties at Room Temperature
(440C hardened at 1040°C, oil quenched and tempered at 300°C)
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Tensile (UTS)
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1965 N/mm²
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0.2% Yield Strength
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1896 N/mm²
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Elongation (50.8mm)
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2% min
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Hardness
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59HRc
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Reduction of Area
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10
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