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
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
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
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.