420LC Tool Steel - 1.2099 - ~X5CrS12 - Technical Data

420 LC a pre-hardened, corrosion resistant plastic mold steel is magnetic in its annealed and hardened condition, showing improved machinability and corrosion resistance compared to 420 FM. It is noted for its high dimensional stability and consistent hardness in all cross sections as well as its good compressive strength, heat conductivity and weldability. For this tool steel grade, further heat treatment is not intended.

Purchase 420 LC Tool Steel Online

Select Your Steel Length below

Imperial and Metric Steel Sizes for Sale

Imperial Steel Size

steel type image
$mart Flat Stock [$mart]

Standardized Precision Blanks

Metric Steel Size

steel type image
Precision Ground Flat Stock Metric, oversize [GFSM O/S]

 

steel type image
$mart Flat Stock Metric [$martM]

Standardized Precision Blanks Metric

You can easily reach out to one of our order consultants to find the exact steel products you need.
chat icon
Any Questions?
Icon of an atom

420 LC Tool Steel: Standard values

Working hardness: approx. 33 HRC (delivery condition)
Delivery condition: max. 330HB

Chemical composition in %

Contains additives..

C

0.050000

0.05

0.050000

0.05
Si

0.200000

0.2

0.300000

0.3
Mn

0.900000

0.9

1.000000

1
S

0.120000

0.12

0.120000

0.12
Cr

12.500000

12.5

12.500000

12.5
Ni

0.400000

0.4

0.450000

0.45

420 LC Tool Steel: Technical Data

Icon of a spanner

420 LC Tool Steel: Technical Properties

Pre-hardened, corrosion resistant plastic mold steel. Magnetisable, excellent machinability and good weldability. Resistant to aggressive plastics and humid conditions. Further heat treatment is not intended.

Icon of a check mark

420 LC Tool Steel: Applications

mechanical engineering, apparatus engineering, plastic processing, injection tools, base plates, assembling parts, molding frames, plastic molds, extrusion tools, valves, steam valves, water valves, fittings parts, pump construction, pump rods, compressor construction, compressor parts, surgical instruments

Chemical designation: Working hardness: approx. 33 HRC (delivery condition)
Delivery condition: max. 330HB

C

0.050000

0.05

0.050000

0.05
Si

0.200000

0.2

0.300000

0.3
Mn

0.900000

0.9

1.000000

1
S

0.120000

0.12

0.120000

0.12
Cr

12.500000

12.5

12.500000

12.5
Ni

0.400000

0.4

0.450000

0.45

Pre-hardened, corrosion resistant plastic mold steel. Magnetisable, excellent machinability and good weldability. Resistant to aggressive plastics and humid conditions. Further heat treatment is not intended.

mechanical engineering, apparatus engineering, plastic processing, injection tools, base plates, assembling parts, molding frames, plastic molds, extrusion tools, valves, steam valves, water valves, fittings parts, pump construction, pump rods, compressor construction, compressor parts, surgical instruments

420 LC General Information

Where can 420 LC be used?

420 LC is used for mold assemblies, mold frames, corrosion resistant tools, basic components but also for tools with high cutting volumes. It can be used for hot runners, support plates, for aggressive plastics, in humid climates and in environments building condensation.

Is the 420 LC a stainless steel?

To be classed as a stainless steel a material has to be alloyed with at least 10.5% chromium. That means the 420 LC is a stainless steel with an alloying content of 12.5% chromium.

Is the 420 LC tool steel corrosion resistant?

The 420 LC can be classed as corrosion resistant as it has a mass fraction of 12.5% chrome. 

420 LC tool steel general corrosion

This corrosion resistant mold steel can be used for the processing of aggressive plastics, in humid climatic conditions and condensation building environments. 

Is tool steel 420 LC magnetizable?

As a martensitic stainless steel the 420 LC has a crystal structure that is ferromagnetic, this makes the 420 LC magnetizable and is suitable for magnetic clamping.

Heat treatment for tool steel 420 LC

As 420 LC corrosion resistant plastic mold steel comes pre-hardened, further heat treatment is not intended and can be used in its as delivered condition.

If it is necessary to heat treat the 420 LC to a higher hardness see “Hardening” below. Higher hardness does reduce toughness and hardenability for this steel grade though.

Soft annealing tool steel 420 LC

Protect and uniformly heat the 420 LC workpiece to a temperature of 1562 - 1616°F (850 - 880°C) and cool them in the furnace.

Stress relieving tool steel 420 LC

Heat the workpiece uniformly to 896°F (480°C) and hold at the temperature for 2 hours, then cool the 420 LC in the furnace or in sand.

Hardening 420 LC tool steel

If further or re-hardening of the 420 LC mold steel is necessary, the steel should be soft annealed before hardening. Heat the parts uniformly to a temperature of 1922°F (1050°C) and hold it for half an hour. To prevent decarburization and oxidation the material should be protected during the hardening process.

Quenching tool steel 420 LC

Cooling the 420 LC in oil, care should be taken that the rate of cooling is not as fast as to distort or crack the material. As soon as the material has been cooled down to 120 - 160°F (50 - 70°C) it should be tempered.

• Oil

Tempering 420 LC tool steel

Double temper the 420LC workpieces for a minimum of 2 hours directly after hardening.

Surface treatment for 420 LC tool steel

Polishing can be one kind of surface treatment, it can help corrosion resistance but has an appealing effect as well. 

Machinability for 420 LC tool steel

Welding tool steel 420 LC

420 LC can be welded without pre or post heating. Fillers should be similar to the chemical composition and mechanical properties of the base metal. No over-hardened heat affected zones are developed around the weld material. As a result, the risk of weld-induced cracking during repairs or later in operation is eliminated. If large weld repairs are done it is recommended to reduce residual stresses by stress relieving the parts at a maximum temperature of 896°F (480°C).

Wear resistance of the 420 LC tool steel

On a scale where 1 is low and 6 is high the 420 LC comes in at 2.

420 tool steel tensile strength

The tensile strength for tool steel 420 LC is approx. 163.1 KSI (0.145KSI = 1MPa). This value is the result from a tensile test to show how much force is needed before the material starts to stretch or elongate before it breaks.

Working hardness for 420 LC tool steel

The working hardness for the 420 LC on delivery is at approx. 308 BHN (33 HRC).

420 LC tool steel specific heat capacity

The specific heat capacity of the 420 LC tool steel at room temperature is at 0.46 J/g-°C (0.109 BTU/lb-°F). This value shows how much heat is needed  to heat 1lb of material by 1 Fahrenheit.

Steel properties for tool steel 420 LC

420 LC tool steel density

Typically the density of 420 LC tool steel is 0.278 lb/in3 (7.7g/cm3) at room temperature.

420 LC tool steel thermal conductivity

The heat conductivity for tool steel 420 LC is at 23.9 W/(m*K) (166 BTU/(h-ft*°F)) at room temperature.

Thermal expansion coefficient for the 420 LC tool steel

This diagram shows how much the 420 LC might expand or contract when the temperatures change which can be very important when working with high temperatures or strong temperature changes.

Medium thermal expansion coefficiente
10-6m/(m • K) At a temperature of
10.25 68 - 212°F
10.72 68 - 392°F
11.14 68 - 572°F
11.58 68 - 752°F
12.02 68 -932°F

Specific electrical resistivity for tool steel 420 LC

The following table shows the electrical resistivity of the 420 LC. 

Table of the specific electrical resistivity
Value At a temperature of
0.65 (Ohm*mm²)/m 68 °F

Is the 420 LC a knife steel?

The 420 LC is not typically classified as knife steel. A good knife steel has a good balance of corrosion resistance, edge retention, chipping resistance and is easy to sharpen. Though the 420 LC has some of those properties others are too low, like the edge retention for example, to make a good quality knife.  

Conclusion

The 420 LC is a great choice for plastic molds offering a great combination of corrosion resistance, wear resistance, dimensional stability as well as machinability. Its good properties give this steel good tool life, high quality finishes and make low maintenance possible.

420 LC tool steel datasheet

As a steel supplier we provide you with the datasheet for tool steel 420 LC in PDF format.

Tool Steel alternatives or equivalent

Search for an alternative Tool Steel with the ABRAMS STEEL GUIDE®

It is possible with just one click to find an alternative or an equivalent steel grade!

We have the solution! (Registration is not needed).

Try it now - find an alternative steel grade and its properties in no time.

Steel comparison - 420 LC Tool Steel - Alternative Equivalent - Steel GuideSteel comparison - 420 LC Tool Steel - Alternative Equivalent - Steel Guide

Disclaimer

The data shown here has been compiled with the greatest diligence and is regularly updated with regard to the correctness and completeness of its content. The content is indicative only and should not be taken as a warranty of specific properties of the product described or a warranty of suitability for a particular purpose. All information presented is given in good faith and no liability will be accepted for actions taken by third parties in reliance on this information. ABRAMS Industries reserves the right to change or amend the information given here in full or parts without prior notice.