4140HW Alloy Steel Technical Data 4140HW Meets AISI4140 Standards and Has Improved Hardenability and Strength in Heavier Cross-Sections

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4140HW Alloy Steel Technical Data 4140HW meets AISI4140 standards and has improved hardenability and strength in heavier cross-sections.

Alloy Description TimkenSteel’s 4140HW grade is a fine-grained, low-alloy steel that offers strength and toughness properties in optimum heat-treat response in heavier cross-sections. You find 4140HW in a both the longitudinal and transverse variety of bar and tubing applications in quenched and tempered conditions. directions of the final product. Yield strengths range from 110 ksi through 140 ksi, but we can temper it to After refining the steel, we teem it into other strength levels. When compared with standard 4140 heat treated to large bottom-poured ingot molds or the same tensile and yield strengths, 4140HW achieves significantly higher continuously cast into large blooms. toughness, as measured by impact strength (see Figure 9). We can roll these ingots or blooms 4140HW combines medium carbon content with high-end chromium, into solid rounds for machining and molybdenum, and manganese contents to improve hardenability. We add forging or for conversion into seamless trace amounts of vanadium to increase temper resistance. Other residual mechanical tubing. elements are also added, but controlled within AISI4140 standard limits. A grain structure enhances toughness at all strength levels. Alloy Type We produce 4140HW using the electric-arc furnace method. After the Hardenable, low alloy steel. melting process, we transfer the molten steel to a ladle refiner for alloy Typical Applications adjustments and vacuum de-gassing. By performing argon stirring under a near-perfect vacuum, we remove impurities and harmful gases. This Oil and gas drilling and completion melting and refining process path reduces levels of tramp elements such equipment such as packers, liner as phosphorus and sulfur. A subsequent calcium treatment spheroidizes hanger components, drilling jars remaining manganese sulfides. The melt-and-refine approach optimizes and fishing tools. Procedure and Results

Chemistry

C Mn Si Cr Ni Mo

Typical 4140HW 0.41 0.98 0.32 1.07 0.15 0.22

Typical 4140 0.42 0.97 0.27 1.04 0.13 0.18

AISI 4140 0.38/ 0.75/ 0.15/ 0.80/ 0.15/ Standard Limits 0.43 1.00 .35 1.10 0.25

Physical Properties

Value (units)

Density 0.284 lb/in3 (7.85 g/cm3)

Thermal Conductivity 296 BTU-in/hr-ft2-ºF (0.106 cal-cm/s-cm2-ºC) at 212ºF (100ºC)

Specific Heat 0.114 Btu/lb/°F (0.16 cal/g/°C) at 122-212ºF (50-100ºC)

Thermal Expansion 6.78 – 8.11 µin/in-ºF (12.2 – 14.6 µm/m-K) at 68-212ºF (20-100ºC) Coefficient

Modulus of Elasticity 29.7 x 103 ksi (205 GPa)

Poisson’s Ratio 0.29

Mechanical Properties

Hardness See Figure 1

Tensile See Figure 2 and Figure 3

Charpy V-notch Impact See Figure 5 and Figure 6

Heat Treatment

Temperatures 1600 – 1700°F (871 – 927°C), Normalize Forced air cool prior to harden/temper Austenitize 1600 – 1650°F (871 – 899°C), Liquid quench, Quench and Temper Temper to desired strength Hardenability

Jominy Hardenability See Figure 10

CCT/IT phase transformations See Figure 7 and Figure 8

Workability

Hot Forgability Forge up to 2250°F (1230°C)

Other Properties

High-Temperature Properties See Figure 4 Figure 1 (Hardness vs. Tempering) This data generated in a laboratory shows the effect of tempering temperature on midwall hardness for 1.25" and 2" wall tubing. Austenitized at 1625°F (885°C) and water quenched. Soak time of approximately 60 minutes at temper temperature.

Figure 2 (Strength vs. Tempering) This data generated in a laboratory shows the effect of tempering on strength for 1.25" and 2" wall tubing. Austenitized at 1625°F (885°C) and water quenched. Soak time of approximately 60 minutes at temper temperature. Figure 3 (Ductility vs. Tempering) This data generated in a laboratory shows the effect of tempering on the elongation and reduction of area for 1.25" and 2" wall tubing. Austenitized at 1625°F (885°C) and water quenched. Soak time of approximately 60 minutes at temper temperature.

Figure 4 (Hot Tensile) This data generated in a laboratory shows high temperature strength of 4140HW for 1.25" - 2" wall tubing. Austenitized at 1625°F (885°C) and water quenched. Figure 5 (L-CVN vs. Tempering) This data generated in a laboratory shows the effect of tempering on the longitudinal impact energy (Charpy V-Notch) for 1.25" and 2" wall tubing tested at -4°F. Austenitized at 1625°F (885°C) and water quenched. Soak time of approximately 60 minutes at temper temperature.

Figure 6 (T-CVN vs. Tempering) This data generated in a laboratory shows the effect of tempering on the transverse impact energy (Charpy V-Notch) for 1.25" and 2" wall tubing tested at +32°F. Austenitized at 1625°F (885°C) and water quenched. Soak time of approximately 60 minutes at temper temperature. Figure 7 (CCT Curve) Predicted isothermal and continuous cooling transformation diagrams for 4140HW calculated with Thermo-Calc.

Figure 8 (CCT Curve) Predicted isothermal and continuous cooling transformation diagrams for 4140 calculated with Thermo-Calc. Figure 9 (Mechanical Properties for 4140 and 4140HW) The data represents a mechanical property comparison of several 4140 and 4140HW heats.

Figure 10 (Jominy Hardenability Curve for 4140 and 4140HW) The data represents an average of Jominy results from several 4140 and 4140HW heats.

For more information, visit www.timkensteel.com or call us at 866.284.6536 (USA), +44 (0) 116 2325186 (Europe), +52 (55) 5876 9888 (Latin America) and +86 (21) 60231080 (China).