1.2345 X50CrVMo51 Hot Work Tool Steel

1.2345 is a 5%chromium hot work tool steel designed particularly for applications requiring extreme toughness combined with good red hardness.It provides an extra margin of safest in tools subject to heavy hammer blows,and those tools containing deep recesses or sharp corners.While 1.2345 has been designed primarily as a hot work tool steel,it has been used in many cold work applications where extra toughness is required at the sacrifice of some wear resistance.

Applications

1.2345 has been used primarily for tools requiring resistance to softening at elevated temperatures.Such tools include forging dies and punches,die-casting dies,aluminium extrusion dies,hot heading dies,piercing and forming punches,etc.

Chemical composition (wt.%)

Mechanical Properties

Physical properties(average values)at ambient temperature

Modulus of elasticity[103x N/mm]:215

Density [g/cm3]:7.70

Thermal conductivity[W/m.K]:25.0

Electric resistivity[Ohm mm/m]:0.52

Specific heat capacity[J/g.K]:0.46

Soft Annealing

Heat to 760-8200C,cool slowly in furnace.This will produce a maximum Brinell hardness of 250.

Stress Relieving

To relieve machining strains for greater accuracy in hardening,first rough machine,then anneal below the critical 649/677C a minimum of one hour at temperature,and cool very slowly,

followed by finish machining.

Hardening

Harden from a temperature of 1000-1040C followed by air,oil warm bath(450-550%C) quenching.Hardness after quenching is 54-58 HRC.

Forging

Heat slowly and uniformly to a temperature of between 1093/1135C and forge.Do not work the steel below 927C.Reheat as often as necessary.

Machinability

The machinability of 1.2345 may be rated between 55%and 65%of a 1%carbon water hardening tool steel,or about 40%to 50%of B1112.

Weldability

To salvage tools and dies by welding,preheat to 538c in a furnace and weld with uncoated arc equipment(atomic hydrogen or heliarc).Keep the temperature of the die above 316C at all times by reheating until the welding is completed.Upon completion of the weld,return the work piece to the preheating furnace,equalize,and cool in the furnace.Welding should be performed in the annealed condition.However,if welding is performed in the hardened condition,the tool should be retempered at 538C after hardening.The electrode material used in the weld rod should be of similar analysis to the base material.