TOZ ENJEKSİYON KALIPLAMA İLE ÜRETİLMİŞ TUNGSTEN KARBÜR PARÇALARDA BAĞLAYICI GİDERME SÜRESİNİN VE PARÇA BOYUTLARININ AĞIRLIK KAYBINA ETKİSİNİN ARAŞTIRILMASI

Yıl 2018, Cilt: 6 Sayı: 1, 75 - 83, 30.04.2018

Kamran Samet Oğuz Yılmaz Harun Koçak Asghar Safarian Çetin Karataş

https://doi.org/10.20290/aubtdb.331088

Cited By: 1

Öz

Toz enjeksiyon
kalıplama (TEK), plastik enjeksiyon kalıplama ve geleneksel toz metalürjisi
tekniklerinin kombinasyonundan ortaya çıkmış bir yöntemdir. Bu metot besleme
stoğunun hazırlanması, besleme stoğunun kalıba enjekte edilmesi, bağlayıcı ayrıştırma
işlemi ve sinterleme olmak üzere dört temel adımdan meydana gelmektedir. TEK’te
bağlayıcı ayrıştırma işlemi, sinterleme sonrasında parçada elde edilecek nihai
mukavemete etki etmektedir. Aynı zamanda bağlayıcı ayrıştırma süresinin
uzunluğu maliyeti arttırmaktadır.  Bundan
dolayı bağlayıcı ayrıştırma işlemi esnasında meydana gelen optimum ağırlık
kaybının tespit edilmesi önemlidir. Bu çalışmada üç farklı kalınlıkta (4,3;
9,75 ve 12 mm) ve uzunlukta (15, 14, ve 11 mm) numuneler WC-% 9Co besleme
stoğundan TEK yöntemi ile üretilmiştir. Daha sonra numuneler 24, 48, 60 ve 72
saat olmak üzere dört farklı sürede, etanol kullanılarak kimyasal bağlayıcı
ayrıştırma işlemine tabi tutulmuştur. Deneyler sonucunda parçanın kalınlığı,
hacmi, yüzey alanı/hacim (Ay/V) oranı ve bağlayıcı ayrıştırma süresinin ağırlık
kaybına etkisi tespit edilmiştir. Çalışma sonucunda ham mukavemetli WC-% 9Co
parçalarda yüzey alanı/hacim (Ay/V) oranı arttıkça ağırlık kaybının da arttığı,
kalınlık ve hacmin artması ağırlık kaybını azalttığı tespit edilmiştir. Etanol
ortamında ve 60°C sıcaklıkta bağlayıcı ayrıştırma işlemi gerçekleştirilen
numunelerde optimum sürenin 60 saat olduğu belirlenmiştir.

Anahtar Kelimeler

TOZ ENJEKSİYON KALIPLAMA, BAĞLAYICI AYRIŞTIRMA, BAĞLAYICI AYRIŞTIRMA SÜRESİ, YÜZEY ALANI/HACİM ORANI

The investigation of the effects of debinding time and dimensions of sample on parts produced from tungsten carbide by powder injection molding

Öz

Powder
injection molding (PIM)  is a method that
is emerged from the combination of conventional powder metallurgy technique and
plastic injection molding. This method, comprises four basic steps including of
preparation of the feedstock, injecting into the mold,the binder removal
process and sintering. The binder removal process in PIM effects the ultimate
strength achieved in part after sintering. Also if the debinding time is selected
as higher than optimum level, production cost will increase, obviously. Therefore,
determination of loss of mass that occurs during binder removal process is
significant. In this study, tungsten carbide (WC) samples with three different
diameters (4,3; 9,75 ve 12 mm)  and three
different lengths (15, 14, ve 11 mm)  were produced by PIM method. Then these
samples were subjected to chemical debinding process at four different time,
24, 48,  60 and 72 hours, respectively.
Ethanol was used as solvent in the chemical binder removal process, As a result
of experiments, the effects of sample thickness, volume, surface area/volume
ratio (A_y / V) and debinding time on weight loss were specified by
using PIM. According to the this study, as the surface area/volume ratio (A_y
/ V) is increased the weight loss will increased, while the  thickness and volume are increased, weight
loss will decreased for the green part of the feedstock. 60 hours is determined
as optimum binder removal parameters for the case of 60°C in ethanol.

Anahtar Kelimeler

Powder Injection Molding, Debinding, Debinding time, surface area/volume ratio

Kaynakça

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