Hardness and wear resistance

A chemical nickel-plating has a hardness of 500-550 HV (52HRC) like hardened steel. It is possible to increase hardness by heat treatment (annealing) of the coated piece with a temperature of 400° C for one hour or at 300°C for 12 hours, obtaining 1200 HV (72 HRC), more than the one that can be obtained with the chromium plating. The heat treatment helps to increase the wear resistance carrying it at the same level of the chromium one.

Coating characteristics

- Adhesion

Coating adhesion is excellent (45 kg/mm²) and more than the one obtained with chromium.

- Corrosion allowance

One of the main characteristics of METALENP treatment is the high resistance to corrosion. A chemical nickel plating, having a very low porosity, completely seals the basic material preserving it from corrosion.

The phosphorus percentage in the alloy is of great importance. In deed, with a high percentage of phosphorus (over 10%) coating has a better resistance to corrosion.

- Friction Factor

Due to annealing and phosphorus self-lubrication property, the friction factor is very low.

- Nontoxicity

Thanks to its high corrosion allowance, the METALEMP treatment does grant nontoxicity.

Which are the material that can be treated?

With the METALEMP chemical nickel-plating every kind of material can be easily plated. In particular:  iron, carbon steel, stainless steel, copper, brass, bronze, aluminum and its alloys. 

property	chemical nickel plating	chromium plating	electrolytic  nickel plating
hardness HV (coated)	500/550	800/1000	220/230
hardness after heat treatment	900/1200	---------	---------
penetrating power	excellent	poor	fair
plating uniformity	excellent	poor	fair
corrosion allowance	excellent	god	fair
wear resistance	excellent	excellent	poor
successive grinding	no	yes	yes
point effect	no	yes	yes
porosity	low	very high	high
Weldability	good	not possible	difficult
oil wettability	excellent	poor	good

Where do you use METALENP  treatment?

Main reasons of the wide use of METALENP chemical nickel-plating are the following:

·      the unique method of plating that allows to plate every piece in every part of it and in an uniform way.

·      the good corrosion allowance in many aggressive environments allowing to replace stainless steel (expensive and difficult to machine) with plated carbon steel

·      the opportunity to plate less-hard materials but easier to be machined

·      the possibility to obtain hardness standards higher than the ones that can be obtained with steel hardening treatments (hardening, casehardening, ammonia /ionic hardening, etc.) or by other superficial treatments

·      the reduction of friction and subsequent increase of the part life

·      the possibility to recycle wear parts, also having complicated shapes (i.e.:  moulds, gears, etc.) and giving them the original shape

·      the possibility to have an excellent aesthetic look

Now, It is easy to understand that the chemical nickel-plating is suitable to every industrial use and mainly for:

car

oil industry

pneumatic

aeronautical

naval

chemical industry

plastic and non plastic moulds

food

heavy and light mechanics

oleo dynamic

mining

textile

pharmaceutical

METALCOATING is FIAT awarded supplier no.903397 graduated 96/100 in the FIAT list of suppliers and 100/100 in the Magneti Marelli list of suppliers.

 

Main customers

Simens

Olivetti

IBM

Magneti Marelli

Zoppas

Parker

FIAT

FORD

 

Chemical instrumentation

·      wide laboratory for chemical research destined to the high phosphorus and corrosion allowance

·      automatic tests of baths and their concentrations with feed-back reset by means of differential digital.

·      continuous pH-meter with range values reset by automatic feed-back.

·      Possibility of PC interface for spectrophotometer, pH-meter and temperature probes for continuous graphic check of daily changes and calculation of setup and solutions

·      digital impulse measurer for baths control according to SCP theory, PC interfaced for Tafel data processing

·      Contact with the Applied Chemistry and Physics Department of the ‘Politecnico di Milano’ for particular analysis and advanced consulting

TECHNICAL DATA – SUMMARY

Chemical nickel METALENP

 

Chemical composition	nickel			87/90%
	phosphorus			13-105
	hydrogen			0.0018%
	nitrogen			0.003%
	oxygen			0.002%
Melting point	890°C
specific weight	7.85g/cm3
Expansion coefficient	13x10-6 cm/cm °C
Comparative data	steel			12x10-6 cm/cm °C
	copper			17x10-6 cm/cm °C
	brass			19x10-6 cm/cm °C
	aluminum			23x106 cm/cm °C
Specific resistance	66m ohm
Magnetic force	METALENP (13% phosphorus)			4%
	electrolytic nickel			36.7%
Young Elasticity index	18000-20000 kg/mm2
Hardness	just coated			500HV
	after heat treatment at 240° C			700HV
	after heat treatment at 340° C			1200HV
Friction coefficient	just coated			0.13 – 585HV
	after heat treatment at 400° C			0.09 – 1200HV
Adhesive force (on steel and copper alloy)	35-48 kg/mm2
Coating uniformity	---+ - mm
Weldability	good
Corrosion allowance (---)	Thickness	10mm	25mm		50mm	75mm
	qty.of pores-hard chrome	many	260		18	10
	qty.of pores-chem.nickel	28	7		1	0
Nontoxicity	assured