What type of steel is best for machining?

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What type of steel is best for machining?

The answer to this question is a lot more complicated than one might think. There are many different types of steel, and each has its own properties and uses.

For example, there are four main types of steel: low-carbon steel, high-carbon steel, alloy steel and stainless steel. Low-carbon steels are used for applications in which the metal will not be subject to great stress or wear; they are also used in applications where the metal must be easy to machine. High-carbon steels have a higher carbon content than low-carbon steels, which makes them harder and stronger; they are also less prone to rusting. Alloy steels contain elements other than iron (e.g., nickel) that provide added strength or corrosion resistance.Stainless steel is less common because it is more expensive and requires more care when machining.

Carbon Steel:

– Low cost

– High hardness

– Lower corrosion resistance

– Easy to machine

Stainless Steel:

– Higher cost

– Lower hardness (but still hard)

– Higher corrosion resistance

What type of steel is best for machining?

1. Stainless Steel

General CharacteristicsAlloyCommon ApplicationsTolerances for a 1/2″ Dia. Bar
Designed for machining, non-magnetic303Electronic hardware, automotive, aerospace, medical instruments, and many applications requiring corrosion resistanceCold finished
+/- .002
Better weldability and formability, slightly more corrosion resistant304Applications needing formability or weldabilityCold finished
+/-.002
Better corrosion resistance316Medical implants and surgical instruments, aerospaceCold finished
+/-.002
Corrosion resistance and high electrical resistivity430 FRExcellent corrosion resistance in fresh water, gaseous, moderately acidic, and low chlorine environments0.002
High carbon, can harden to RC 60440Applications requiring stainless steel with highest hardness0.002
Excellent corrosion resistance and heat treatable17-4 PHMedical, aerospace, applications needing corrosion resistance and hardness+/-.002

2. Steel

General CharacteristicsAlloyCommon ApplicationsTolerances for a 1/2″ Dia. Bar
Moderate strength and low-stress applications.1008Good matte surface finish that makes it suitable for exposed parts0.002
Plain low carbon steel, poor machinability but good formability and weldability. Case harden only1018Rivets and parts requiring strong weldsCold drawn
0
Strength, impact resistance and higher tensile strength. 1045Responds to heat treatment extremely well, but it not recommended for case hardening0.003
Higher carbon, higher strength, direct hardening1137Higher stress applications, gears, shafts, studs, etc.Cold drawn
0
Strength and machinability11L37Easily machined and can be annealed, quenched, tempered, and heat treated0.003
Strength and hardness and a more uniform surface hardness11L41Axles, shafts, bolts, and pins0.003
Designed for excellent machinability. Case hard only12L14Endless commercial products; probably more pounds used in turned products than any other bar stockCold drawn
0
Designed for good machinability. Case harden only1215Parts needing better formability or weldability than 12L14Cold drawn
0
Strength, toughness, and fatigue resistance4130Military and commercial aircraft partsNorm AQ
HT Condition F4
Popular general-purpose alloy. Direct hardening4140 or 4142Gears, shafts, pins, bolts and nuts, pump and valve componentsCold drawn
0
Designed for better machining w/lead additive; direct hardening41L40Couplings, shafts, tooling, boltsCold drawn
0
.55% Ni, .50% Cr, .20% Mo, heat treatable and case hardening8620Shafts, bushings, pins, gears, boltsCold drawn
0
Very high 1% carbon, .25% Ni,1.4% Cr, .08% Mo52100Bearing applicationsCold drawn
Spheroidize annealed
+/- .006

What Type Of Steel Is most popular For CNC Machining?

Carbon Steel: Carbon steel is the most common type of metal used for CNC machining because it has the highest level of ductility and toughness. Carbon steel has less resistance to corrosion than stainless steel but can be more easily welded than stainless or tool steels.

Stainless Steel: Stainless Steel is also a popular choice for CNC machining because it’s resistant to corrosion, rusting, tarnishing, and other chemical reactions with air or water, and it’s food grade material that can be used food processor and storage containers/equipments.

Author: Mose Li

Author: Mose Li

Director of Project Engineering at 3Q Machining