| 摘要 |
Apparatus for identifying the metal alloy composition of a test piece. Two thermoelectric probes are brought into contact with the test piece. Both of the probes are heated, one of which is heated to a predetermined temperature greater than the temperature of the other probe. The probes comprise electrodes of a thermally conductive material having in thermoelectric contact therewith, respective thermoelectric circuits having differing predetermined thermoelectric characteristics. A variable voltage divider electrically couples the respective thermoelectric circuits of the two probes. The output terminals of the voltage divider networks are connected in series opposition through a null meter or indicator which displays the test result. The voltage divider networks of the respective probes are mechanically or electrically slaved such that they are adjusted in synchronism, thereby desensitizing the apparatus to changes in test temperature, ambient temperature or the temperature of the respective test pieces. Further, simple calibration means are described and additionally, provisions for establishing further discriminants between alloys by (1) the use of different metal probe contact tips, (2) application of a magnetic field to encompass the probe/test piece junction, (3) momentarily varying the temperature of one of the electrodes through a Peltier effect, (4) generating biasing voltages across the probe/test junctions, and (5) comparing voltage-ampere ratio's of each alloy. One or a combination of such features may serve to alter and/or reveal thermoelectric characteristics for discriminating between alloys of similar chemical composition or to confirm the identity of known metal alloys or to establish positive identification of metals of unknown chemistry or to detect alloying segregation in high quality metal products.
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