UGICHROM® 4462: High-Performance Micro-Fissuring Chromium Plating for Hydraulic & Pneumatic Systems

UGICHROM® is the result of combining the high efficiency of micro-fissuring chromium plating with the technology of the most advanced stainless steel bars. The UGICHROM® product range is recommended for hydraulic and pneumatic mechanisms.

General properties - choice for performance:

Low friction coefficient.

High resistance to wear.

Increased corrosion resistance.

Micro-fissuring chromium plating guarantees excellent performance under extreme conditions of service.

Improved machinability (up to +20% of productivity).

High mechanical properties.

Accurate geometrical and dimensional properties..

Properties

General

Property	Value
Density	7.8 g/cm³

Mechanical

Property	Temperature	Value
Elastic modulus	20 °C	200 GPa
	100 °C	194 GPa
	200 °C	186 GPa
	300 °C	180 GPa
Tensile strength		650.0 - 880.0 MPa

Thermal

Property	Temperature	Value	Comment
Coefficient of thermal expansion		0.000013 1/K	20 to 100°C
		0.0000135 1/K	20 to 200°C
		0.000014 1/K	20 to 300°C
Specific heat capacity	20 °C	500 J/(kg·K)
	100 °C	530 J/(kg·K)
	200 °C	560 J/(kg·K)
	300 °C	590 J/(kg·K)
Thermal conductivity	20 °C	15 W/(m·K)
	100 °C	16 W/(m·K)
	200 °C	17 W/(m·K)
	300 °C	18 W/(m·K)

Electrical

Property	Temperature	Value
Electrical resistivity	20 °C	0.0000008 Ω·m
	100 °C	0.00000085 Ω·m
	200 °C	0.0000009 Ω·m
	300 °C	0.000001 Ω·m

Chemical properties

Property	Value	Comment
Carbon	0.03	max.
Chromium	22.0 - 23.0 %
Manganese	1.0 - 2.0 %
Molybdenum	2.5 - 3.5 %
Nickel	5.0 - 6.0 %
Nitrogen	0.12 - 0.2 %
Phosphorus	0.035	max.
Silicon	0.75	max.
Sulfur	0.01 %	max.

Technological properties

Property

Application areas

Hydraulic and pneumatic mechanisms

Corrosion properties

As UGICHROM® is "stainless in mass" there are no corrosion resistance problems over time, provided that the chosen grade is appropriate to the place of use.

Passive layer: Stainless steels produce a very fine surface film of oxide consisting of chromium oxides and hydroxides a few Angströms thick. This oxide, commonly called a passive layer, protects the stainless steel against external attacks and gives it the property known as inoxidibility which guarantees the corrosion resistance of these alloys. The passive layer is an intrinsic part of the material, unlike the "Nickel-Chromium" coating deposited on carbon steels, which explains why stainless steel exhibits the basic corrosion resistance and adhesion advantages of chromium under harsh mechanical operating conditions (buckling). Once formed, this passive layer is completely stable since its thickness remains constant. The passive layer inhibits any exchange between the metal and the outside: in the event of damage to the material (scratch, cut, impact, drilling, deformation, etc.), it reforms spontaneously. This self-restructuring is also called "Repassivation".

Choosing the most suitable grade: Only choosing the grade that is most appropriate to the operating environment increases the durability of hydraulic cylinders, depending on use. The figure on the right side of the material page shows how to obtain the best compromise between mechanical strength and corrosion resistance (see the chart on the right side of the material page).

Other

The mechanical properties of UGICHROM® are suitable for all hydraulic applications:

CHARACTERISTICS	Standard product	Special product
Diameter tolerance	ISO f7	On request
Bar length dia. 12 to 19 mm	2900 mm +200/-0	On request
Bar length dia. 20 to 125 mm	6000 mm +/- 500 mm	On request
Roundness	<1/2 f7 ISO
Straightness (to EN 10278)	<0.5 mm/ml	Up to 0.2 mm for dia. >30 mm
Roughness	Ra < 0.2 µm	Up to Ra <0.08 µm
Chromium structure	Microcracked
Sizes	Dia. 12 to 125 mm	On request
Thickness of the chromium dia. 12 to 19.5 mm	18 µm +/-3	Max. 50 µm
Thickness of the chromium dia. 20 to 115 mm	25 µm +/-5	Max. 100 µm