The discrepancy between 4140 and 41L40 alloys is also discussed in terms of what 41L40 steel and 41L40 steel properties are.
What is the Steel 41L40?
Steel alloy 41L40 is chromium-molybdenum steel free-machining with a lead addition, which makes it easy to machine, but also contributes to lower impact strength than other steel alloys. High strength, high hardness, high ductility, high wear resistance, strong durability, and resistance to stress and creep at sustained high temperatures are available in 41L40 steel. Heat treatment and annealing of 41L40 can be performed. 41L40 is suitable for components requiring high resistance to wear and power. It is also used with CNC milling/turning technologies for producing shafts, bolts, couplings, tractor & trailer axles, spindles, and tooling. Quality CNC machining parts from 41L40 Steel can be given by Junying.
Composition of 41L40 Grade Alloy
Phosphorus (max): 0.035
Sulfur (max): 0.035
Nickel (max): 0.030
41L40 vs 4140 - Difference Between 4140 and 41L40
A letter along with the digit is used by the AISI system to denote the steel making process, the prefix "C" indicates open-hearth furnace, electric arc furnace, or basic oxygen furnace, "E" implies electric arc furnace steel, while "L" denotes lead as an added ingredient within the alloy grade name, so 41L40 is the lead added variant of the common grade 4140 for machinability improvement.
The lead grade has greatly improved machinability, but is not ideal for use in applications above 400 ° F because lower ductility is induced by increased temperatures. To accomplish equal hardness and strength, 41L40 can be heat treated the same as a regular 4140. For the lead grade, the impact strength for hardnesses exceeding 35 HRC is much lower.
What is the 4140 type of steel? The low-alloy steel containing chromium, molybdenum, and manganese is steel 4140 (AISI 4140). Due to its excellent performance such as durability, high fatigue strength, and abrasion and impact resistance, typical applications like structural tubing, bicycle frames, gas bottles, firearm components, flywheel components, and more, it is widely used in a wide range of industries. Let us clarify the SAE steel family's designation scheme. A four-digit number is allocated for carbon steels and alloy steels, with the first digit indicating the main alloying element(s), the second digit indicating the top-grade element, and the last two digits indicating the quantity of carbon. The steel of the 4xxx series is a type of Molybdenum steels, while the grades of the 41xx series are Chromium-molybdenum steels, the Society of Automotive Engineers specifies 41xx steel.
4140 Steel Properties
Density: 7.85 g/cm3
Melting point:1416 ℃
Tensile strength: 95000 psi
Yield strength: 60200 psi
Elastic modulus: 27557-30458 ksi
Hardness, Brinell: 197
Hardness, Rockwell B: 92
Hardness, Rockwell C: 13
Hardness, Vickers: 207
41L40 Steel Properties
Reduction of area (%): 50-60
Brinell Hardness (BHN): 200-230
Tensile strength: 95,000 – 105,000 psi
Yield strength: 85,000 – 95,000 psi
Elongation in 2” (%): 15-25