Browse Prior Art Database

Metallic Coating Thickness Measurement

IP.com Disclosure Number: IPCOM000060157D
Original Publication Date: 1986-Mar-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 2 page(s) / 59K

Publishing Venue

IBM

Related People

Argyle, BE: AUTHOR [+3]

Abstract

In various types of circuits and packaging, metal coatings (such as palladium/gold) are used on magnetic alloy connector pins. These pins are often soldered and must withstand a given pull strength in order to exhibit suitable connector behavior. However, pins having an excess thickness of the coating layer often do not exhibit sufficiently high pull strengths. The apparatus shown in Fig. 1 nondestructively discriminates between the different thicknesses of the coating on these pins and accurately detects pins having unsuitable cladding thickness. In Fig. 1, the pin 10 is inserted into a transformer coil arrangement with primary and secondary windings imbedded into epoxy for mechanical integrity.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

Metallic Coating Thickness Measurement

In various types of circuits and packaging, metal coatings (such as palladium/gold) are used on magnetic alloy connector pins. These pins are often soldered and must withstand a given pull strength in order to exhibit suitable connector behavior. However, pins having an excess thickness of the coating layer often do not exhibit sufficiently high pull strengths. The apparatus shown in Fig. 1 nondestructively discriminates between the different thicknesses of the coating on these pins and accurately detects pins having unsuitable cladding thickness. In Fig. 1, the pin 10 is inserted into a transformer coil arrangement with primary and secondary windings imbedded into epoxy for mechanical integrity. This arrangement acts as a transformer having 1:1 ratio, four-turn, coils in which the pin 10 which acts as the core can be inserted and removed easily. Pin 10 is comprised of a magnetic alloy having a palladium/gold cladding. This circuit accurately measures the feedthrough of the signal by the pin/coil assembly in order to distinguish pins having different thicknesses of cladding. The input portion 14 of the transformer coils is connected via a coax cable or transmission line 16 to an RF amplifier 18 which, in turn, is connected to an RF signal generator 20. The output portion 22 of the transformer coil is connected to a transmission line 24 which is connected to an RF spectrum analyzer 26 which provides inputs to x-y plotter 28. Signal generator 20 and spectrum analyzer 26 are frequency locked to one another as illustrated schematically by the interconnection 30. Fig. 2 plots the feedthrough signal obtained versus the frequency of the applied RF signal for different types of pins inserted in the transformer coil arrangement. Curve a illustrates the signal when no pin is present in the transformer coil, i.e., air coupling of the input portion 14 and the output portion 22. Curve b represents the feedthrough signal obtained when a cladd...