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With the aid of Chalmers specimens according to DIN ISO 4368, part 2, the bonding strength between Babbit sliding bearing materials and steel support members was investigated. The experimental results proved that the bonding strength of the newly developed alloy Sn-12Sb-6Cu-1.8Bi remained insufficient, when the supporting shell of steel grade C 10 was dipped in a pure Sn bath, even with variations of Sn bath temperature or casting and cooling modifications. With Bi containing melts an oxide layer forms between steel and bearing metal when the alloy is poured into the tin coated cups requested for Chalmers specimens. This oxide layer prevents a proper Fe/Sn bonding. The reason for the formation of the oxide layer when using Bi containing melts is not understood. A possible solution to the bonding problem is the in situ formation of a new bond coating directly from a modified tin bath. To this end, the bath of pure tin is alloyed with an element which has a higher affinity to iron than tin does. One possible alloying element is Zn, which can form intermetallic Fe-Zn layers on the steel shell enabling higher bonding strengths than layers formed in pure tin baths. By modifying the tinning of steel support shells this way, the originally low bonding strength of the newly developed bearing alloy could be increased to the level of conventional tin based sliding bearing alloys. In addition, the bonding strength of conventional Babbit metals on tin base could be considerably increased. The modified Sn Zn bath yields high bonding strengths with the investigated new alloys Sn-12Sb-6Cu-1.8Bi, Sn-12Sb-6Cu-1.8B+Te5, Sn-12Sb-6Cu-1.8B+Ni5, Sn-12Sb-6Cu-1.8Bi+Zn50 as well as with the conventional Babbit alloys TEGO V738, TEGOSTAR and TEGOTENAX. With the lead based alloy LM-THERMIT an improvement is not achieved, yet, the bonding strength surpasses under all testing conditions a value of 50 N/mm2. This proves that the new bath is universally applicable. To test the alloy dependence of the bonding strength the Zn content was varied from 9 over 24, 50 and 60 to 70 weight - %. Depending on ZN content the bath temperature was raised from 280 to 380°C. On an average, the Zn content of 50% gave the most favorable strength values. As a bath temperature, 360°C turned out to deliver the best results.

In order to dissipate the heat generated in electronic packages, suitable materials must be developed as heat spreaders or heat sinks. Metal matrix composites (MMCs) offer the possibility to tailor the properties of a metal (Cu) by adding an appropriate reinforcement phase (SiC) to meet the demands for high thermal conductivities in thermal management applications. Copper/SiC composites have been produced by powder metallurgy. Silicon carbide is not stable in copper at the temperature needed for the fabrication of Cu/SiC. The major challenge in development of Cu/SiC is the suppression of this reaction between copper and SiC. Improvements in bonding strength and thermo-physical properties of the composites have been achieved by a vapour deposited molybdenum coating on SiC powders to control the detrimental interfacial reactions. Entnommen aus TEMA

Mit Kombinationen aus einem nichtemulgierten Diisocyanat und Rindenextraktloesungen wurden Sperrholzproben verleimt. Die Zugabe von Paraformaldehyd zu den Klebgemischen erhöhte die Bindefestigkeiten der Sperrholzproben deutlich.