Printer-friendly version
Glossary of MinSE


Browse the glossary using this index

Special | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O
P | Q | R | S | T | U | V | W | X | Y | Z | ALL

Page:  1  2  (Next)
  ALL

B

:

One type of source deployed in magnetron sputter deposition. The balanced magnetron is a standard magnetron sputter cathode in which the outer magnetic field is balanced to match that of the inner field. Until the mid-late 1980's all magnetron cathodes were of this design. The term has been invoked to differentiate this type of magnetron from the more recently developed unbalanced magnetron. Balanced magnetrons are still widely used for coating semi-conductor devices but are less popular for the deposition of tribological coatings, since the substrate current density is low and auxiliary hating is needed to assure adequate coating adherence. Also see unbalanced magnetron.

Hungary flag Kiegyensúlyozott magnetron

:

A controlled polishing technique enabling the ready measurement of coating thickness; especially for thin (≈ 1-10µm) ceramic coatings. A hardened steel or cemented carbide ball, ≈ 20 to 50 mm diameter, is coated with 1µm diamond paste and rotated on the coated surface until the coating is worn through. Since the diameter of the ball is known, a taper section of known geometry is obtained. The width of the wear scar is easily measured with a light-optical microscope and the coating thickness calculated. The method gives good results for coatings that are 1 µm thick or greater.

Hungary flag Kráterképződéses teszt

:

The father of modern surface engineering who pioneered the exploitation of glow discharge plasmas for plasma nitriding and sputter deposition. His patents, originating during the 1930's and continuing through to the 1960's can be regarded as truly seminal. He was born of German parents in Amsterdam on 31st July 1896 and died in Zurich on 30th December 1966. Much of his early life was spent in Munster, N.R.W., Germany. He subsequently established a small research and development company called Gesellschaft zur Forderung der Glimmentladungsforschung whose sole goal was to achieve the industrial exploitation of plasma assisted techniques. Further impetus was provided by a subsequent collaboration with Ionon of Koln (Cologne) which in turn lead to the foundation of Klockner Ionon who transferred plasma nitriding on a major scale to the European and Norh American manufacturing sectors. In later years many other companies emulated the ideas of Berghaus, and today plasma techniques, especially plasma nitriding, is practised in all technologically advanced countries.

Hungary flag Berghaus, Bernhard

:

Hardness determined using a triangular base pyramid diamond indenter. The included angle at the apex of the pyramid is 65°, i.e., the angle between the vertical axis and each of the three faces. The Berkovich indenter is proving popular in nanoindentaion hardness.

Hungary flag Berkovich keménység

:
A proprietry gaseous austenitic nitrocarburising treatment.
Hungary flag Beta
:
The usual configuration of sputter deposition, whereby a negative bias is applied to the substrate during sputter deposition, the purpose of which is to raise the substrate ion density, causing heating and much improved coating adherence. The chamber walls are held at positive-ground potential. The magnitude of the substrate negative bias depends upon the type of sputter source and the point of time in the coating cycle. At the commencement of the treatment, a large negative bias (≈1000 volts) maybe applied to effect a "clean-up" of the components surfaces, through glow discharge sputtering. At the commencement of sputter deposition, the substrate bias voltage is reduced: (i) for a conventonal balanced magnetron source to ≈500 volts; (ii) for a modern unbalanced source to ≈ 50 - 200 volts. Also see balanced magnetron and unbalanced magnetron.
Hungary flag
:
(i) The main component of a polymeric coating material, which binds the pigment and filler particles together and creates a durable bond with the substrate. Also known as a film former. (ii) The metallic Co phase in WC-Co spray deposited coatings.
Hungary flag Kötőanyag
:
A surface finishing process leading to the formation of a thin black oxide film on the surface of a metallic object, performed with the aim of improving corrosion resistance, usually for decorative applications. Steel objects are most frequently blackened in an oxidizing bath or furnace.
Hungary flag Feketedés
:
A technique of non-eqilibrium carburising to enable rapid carbon transfer. See vacuum carburising and plasma carburising.
Hungary flag Gyors-diffúz kör
:
This thermochemical treatment involves diffusing interstitial boron into (mainly) steel or cemented carbide components at a temperature such that highly durable surface mono- or multi-layers of transition metal borides are formed through a reaction between the boron and one or more metals in the substrate. For steels, treatment temperatures are in the range of 750 to 1050°C; for cemented carbides temperatures are ≈1000°C. Other substrates, like titanium and nickel base alloys can be treated in principle but industrial boriding of these alloys is comparatively rare. Various boriding media are available: plasma, gas, salt bath (electroless and electrolytic), pack and paste. Salt bath media are mainly exploited in Eastern Europe; their negative environmental draw backs has prevented wider exploitation in Western Europe, North America and Japan. The main-stay technique outside Eastern Europe remains the pack process, despite notable development efforts in gaseous and plasma boronizing. A common pack comprises (by weight) 90% SiC, 5% B4C and 5% KBF4. The SiC acts as a diluent, the B4C acts as the principal boron source while the KBF4 serves as an activating and fluxing agent. The latter can be satisfactorily replaced by NH4Cl. Boriding has the ability to convey improvements in wear resistance while simultaneously imparting resistance to corrosion by mineral acids and molten metals (especially zinc and aluminium). Boride layers produced through boriding tend to lack the toughness required for high contact loads especially those delivered at high strain rates; in this regard they are inferior to nitrided or carburised steels. The duplex FeB/Fe2B produced on boriding steels, under moderate boron potential, results in the creation of detrimental residual elastic stresses in the vicinity of the FeB/Fe2B interface. This is one factor that is responsible for the observed brittleness of borided surfaces. In the case of plain carbon and low alloy steels, boride layer toughness can be improved by boriding under low boron potential to produce a mono-phased layer of Fe2B. Another possibility is to conduct a post boriding annealing treatment ≈850°C, in vacuo, thereby converting the duplex FeB/Fe2B into a mono-phased Fe2B layer. The latter option is obviously less economic.
Hungary flag Boridálás

Page:  1  2  (Next)
  ALL


Theme by NewSchool Learning