Nuri DURLU, Emre AVŞAR, Aytaç ATAŞ, Cengiz BOZACI, Hüsnü ÖZDURAL

Demir esaslı toz metal parçaların sinterleme ile birleştirilmesi

Bu çalışmada demir esaslı tozların ham ve ön sinterlenmiş halde mekanik geçme sonrası sinterleme ilebirleştirilmesi incelenmiştir. Deneylerde presleme basıncı olarak 600 MPa kullanılmış ve sinterleme işlemleriendogaz ortamında ve indirgeyici gaz karışımında (%90$N _2$ + %10$H _2$) 1120˚C’de 45 dakika süre ile yapılmıştır.Demir esaslı tozların (Fe-%0,6P, Fe-%0,6P-%2Cu, Fe-%0,6P-%3Cu-%0,4C) ham halde ve sinterlenmiş haldemekanik özellikleri ölçülmüştür. Sinterleme ile birleştirme işlemlerinde burç-pelet geometrisi kullanılmıştır.Demir esaslı tozlardan preslenerek hazırlanan burç (Fe-%0,6P, Fe-%0,6P-%2Cu) ve pelet (Fe-%0,6P-%3Cu- %0,4C) numuneler ham ve ön sinterlenmiş halde mekanik geçme sonrası sinterlenerek birleştirilmiş ve bağdayanım değerleri ölçülmüştür. Ham halde sinterleme ile birleştirilen burç-pelet toz metal parçalarınınarayüzeyleri optik ve taramalı elektron mikroskobu ile incelenmiştir. Çalışma sonucunda ham halde mekanikolarak geçirilen parçaların sinterleme ile birleştirme işlemlerinin yeterli düzeyde bağ dayanımı sağladığıbulunmuştur.

Joining of iron based powder metallurgy parts with sintering

In this study, joining of iron based green and pre-sintered powder metal parts by sintering was examined.Samples were pressed at 600 MPa and sintered at 1120ºC for 45 minutes under reducing (%90$N _2$ + %10$H _2$) andendogas atmospheres. Mechanical properties of iron based powder samples (Fe-%0.6P, Fe-%0.6P-%2Cu, Fe- %0.6P-%3Cu-%0.4C) were measured under green and sintered conditions. In joining with sintering experimentsring-pellet geometry was utilized. Green and pre-sintered ring (Fe-%0.6P, Fe-%0.6P-%2Cu) and pellet (Fe- %0.6P-%3Cu-%0.4C) samples were joined by sintering and their bonding strengths were measured. Theinterface formed after sinter joining was examined with optical and scanning electron microscopy. The studyshow that green parts can be joined by sintering without an appreciable loss in bonding strength.

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