Alloy K500 is a precipitation-hardenable nickel-copper alloy which is also known as Monel K500 (Monel® is Special Metals Corporation’s trademark for a family of Nickel-Copper alloys). Although Langley Alloys supply Alloy K500 in all conditions, we predominantly supply material in the hot worked and precipitation treated condition. Both forms offer the optimum combination of high strength and ductility across the size range. The increased properties are obtained by adding aluminium and titanium to the nickel-copper base, and by heating under controlled conditions so that particles of ‘ϒ’ Ni3 (Ti, Al) are precipitated throughout the matrix. The thermal processing used to effect precipitation is commonly called age hardening or ageing.
This alloy provides excellent corrosion resistance in a range of environments including sea water, hydrofluoric acid, sulphuric acid and alkalis. It has found to be resistant to a sour-gas environment and is listed within NACE MR1075. The combination of very low corrosion rates in high-velocity sea water and high strength make it well-suited for marine shafts in stagnant or slow-moving sea water, fouling may occur followed by pitting but this pitting slows down after a fairly rapid initial attack.
Alloy K500 is refined by Electro Slag Refining (ESR), ensuring the cleanest and highest quality of material is supplied. This increased alloy purity limits the likelihood of hard non-metallic inclusion that can increase machining difficulty, processing times and ultimately part failures. It also has low permeability and is nonmagnetic to temperatures as low as -150°F (-101°C).
|Cold Worked & Precipitation Treated||Cold Worked, Solution Treated & Precipitation Treated||Hot Worked & Precipitation Treated||Hot Worked, Solution Treated & Precipitation Treated|
|Bars up to and including 25mm section size or diameter||Bars between 25-55mm section size or diameter||Bars up to and including 25mm section size or diameter||Bars between 25-55mm section size or diameter||Bars up to and including 110mm section size or diameter||Bars between 110-300mm section size or diameter||Bars up to and including 25mm section size or diameter||Bars between 25-110mm section size or diameter||Bars between 110-300mm section size or diameter|
|0.2% Proof Stress||760 (110)||690 (100)||620 (89.9)||550 (79.8)||724 (105)||724 (105)||500 (72.5)||585 (84.8)||500 (72.5)|
|Tensile Strength, N/mm2 (ksi)||1000 (145)||970 (140.6)||900 (130.5)||830 (120)||965 (140)||965 (140)||830 (120.3)||900 (130.5)||830 (120.3)|
|Elongation, 5.65√S0 and 4D||14%||16%||20%||20%||20%||20%||15%||20%||15%|
|Hardness (Rockwell C)||27-35||27-35||27-35||27-35||27-35||27-35||27-35||27-35||27-35|
|Impact Strength (-29oC or lower)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)||27J av (20J min)|
|Magnetic Permeability (20°C)||<1.005 (1.002 typical)|
|Young’s Modulus (kN/mm2)||179|
|Specific Electrical Resistance, 20°C (µΩ-m)||0.62|
|Mean coefficient of thermal expansion, 20-100°C (m/m/degC)||13.4 x 10-6|
|Specific Heat, 20°C (J/kg.K)||418|
|Thermal conductivity, 20°C (W/m.K)||17.5|
|Curie Temperature (°C)||-90|