Abstract: Trivalent Cr layers are
studied by direct current brush-plating and pulse current brush-plating.
Under the SEM, the appearance, the morphology of cross sections
and normal sections of the layers are observed and analysed, the
hardness, bond intensities and corrosion-resistance are
measured. Then the election-probe and X ray diffraction
instruments are used to study the bond and harden mechanism of
layers. The result of research shows that: the harden effect of
the layers if caused by the extra-fine grains and internal
stress in the layers. And the layers and basis are joined by
mechanical bond, metal bond and diffuse bond. All these kinds of
bonds lie on different places of interface, they make the layers
and base metal unit well.
Key words:
Brush-plating Trivalent Cr Pulse
brush-plating Mechanism
Manuscript received on July
6, 1995
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