MAXI MELT offers a full range of single and twin screws. Based on our extensive experience we offer different materials types and treatments to fight wear. The materials range from nitriding steels, stainless steels, tool steels up to steels produced by powder technology (PM).
Welding on screw flights
Name | Base alloy | Alloy components | Hardness (hrc) | Abrasion resistance | Corrosion resistance |
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Stellite 1 | Cobalt | C, Cr, W | 52 – 57 | xxx | xxx |
Stellite 12 | Cobalt | C, Cr, W | 44 – 48 | xx | xxx |
Colmonoy 57 | Nickel | C, Si, Cr, B, Fe | 52 – 56 | xxx | xxxx |
Colmonoy 83 | Nickel | Tungsten carbide | 56 – 60 (x) | xxxxx | xxxx |
CastoTIG5 | Iron | Cr, V | 58 – 62 | xxxx | xx |
Suitability: (x good) to (xxxxx excellent). (x) Tungsten carbides have a hardness of 89 HRC. Other materials on request.

The modification of the screw geometry can improve the plasticizing process and, also, can increase its durability. The MAXI MELT screw profile offers a lower compression ratio against a standard 3 zone screw and therefore also will offer a longer life than a standard 3 zone profile.
Screw coatings
Coating | Thickness of layer (mm) | Hardness | Abrasion resistance | Corrosion resistance |
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Chrome plating | 0,020 – 0,035 | 800 – 1100 HV 0,1 | xxxx | xxx |
Nikel plating | 0,015 – 0,025 | 500 – 600 HV 0,1 | xx | xxxxx |
PVD, TiN | 0,004 | 2500 HV 0,5 | xxx | xx |
PVD, CrN | 0,004 | 2100 HV 0,5 | xxx | xxx |
PVD, CrN-multi layer | 0,008 | 2100 HV 0,5 | xxxx | xxxx |
Suitability: (x good) to (xxxxx excellent)
Base materials for plastizing screws
DIN standard | Material | Type steel | Treatment | Hardness | Abrasion resistance | Corrosion resistance |
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1.8509 | 41CrAIMo7 | Nitriding steel | Nitrided | 950 – 1150 HV 5 | x | x |
1.8550 | 34CrAINi7 | Nitriding steel | Nitrided | 950 – 1150 HV 5 | x | x |
1.4122 | X35CrMo17 | Nitriding steel | Nitrided | 1000 – 1100 HV5 | x | xxx |
1.2379 | X155CrVMo121 | Tool steel | Hardened | 59 – 63 HRC | xxx | xx |
– | KPM1 | PM material | Hardened | 58 – 63 HRC | xxxxx | xx |
– | KPM2 | PM material | Hardened | 55 – 62 HRC | xxx | xxxx |
Suitability: (x good) to (xxxxx excellent). PM is powder material. Other materials on request.