Sains Malaysiana 39(1)(2010): 77–82

Pencirian Titanium Berbusa yang Dihasilkan pada Suhu Pensinteran

yang Berbeza Menggunakan Kaedah Buburan

(Characterisation of Titanium Foams Sintered at Different Temperatures

Prepared by the Slurry Method)

 

S. Ahmad

Fakulti Kejuruteraan Mekanikal dan Pembuatan, Universiti Tun Hussein Onn Malaysia

Batu Pahat, Johor, Malaysia

 

N. Muhamad*, A. Muchtar , J. Sahari, K.R Jamaludin, M.H.I. Ibrahim, N.H. Mohamad Nor & Murtadhahadi

Fakulti Kejuruteraan dan Alam Bina, Universiti Kebangsaan Malaysia

43600 Bangi, Selangor D.E.Malaysia

 

Received: 20 November 2008 / Accepted: 6 July 2009

 

ABSTRACT

 

Kertas ini membentangkan hasil kajian terhadap sifat mekanikal dan fizikal titanium berbusa yang disinter pada suhu yang berbeza. Untuk kajian ini penghasilan titanium berbusa adalah menggunakan kaedah buburan dan menggunakan dua jenis titanium iaitu titanium tulen dan titanium aloi (Ti6Al4V). Buburan titanium disediakan dengan mencampurkan serbuk titanium, polietilena glikol (PEG), metilselulosa dan air. Setelah buburan titanium disediakan, busa poliuretana (PU) direndamkan di dalam buburan tadi dan kemudiannya dikeringkan di dalam ketuhar. Langkah terakhir adalah proses pensinteran yang dilakukan di dalam relau vakum. Suhu pensinteran adalah 1200oC, 1250oC dan 1300¡C. Selepas sampel titanium berbusa diperolehi, ujian kekuatan mampatan dilakukan ke atasnya. Saiz liang dan sangga diukur dengan menggunakan mikroskop elektron imbasan (SEM). Saiz liang yang didapati adalah antara 388 μm hingga 1.07 mm dan saiz sangga adalah antara 59.4 μm to 227 μm. Nilai kekuatan tertinggi didapati untuk sampel yang telah disinter pada suhu 1250oC iaitu 14.85 MPa bagi titanium aloi. Hasil ujian ketumpatan pula adalah berbeza dengan ujian kekuatan mampatan iaitu titanium tulen memberikan ketumpatan yang paling tinggi iaitu 1.25 g/cm3 pada suhu 1300oC diikuti dengan peratusan keliangan sebanyak 65.05% untuk sampel yang sama. Secara keseluruhannya, suhu pensinteran 1250oC didapati paling sesuai untuk kedua-dua titanium tulen dan asli.

 

Kata kunci: Kekuatan mampatan; ketumpatan; keliangan; titanium aloi

 

ABSTRACT

 

The mechanical and physical propertics of titanium foam sintered at different temperatures are reported in this paper. In this work, the slurry method has been used for the production of titanium foams using pure titanium and titanium alloy (Ti6Al4V). The titanium slurry was first prepared by mixing the titanium powder, polyethylene glycol (PEG), methylcellulose and water. Polyurethane (PU) foams, which acted as scaffolds were then impregnated in the slurry, followed by drying at room temperature. These were later sintered in a high temperature vacuum furnace at 1200oC, 1250oC and 1300¡C. The resultant titanium foams were characterised using Scanning Electron Microscopy (SEM) and the compressive strength test. The range of pore sizes obtained was between 388 μm to 1.07 mm, with a strut size in the range of 59.4 μm to 227 μm. The highest compressive strength obtained was 14.85 MPa. This was for the titanium alloy foam which had been sintered at 1250¡C. The highest density (1.25 g/cm3) obtained was for the pure titanium foams that were sintered at 1300¡C. For these, the porosity was found to be 65.05%. In general however, the most suitable sintering temperature was found to be 1250¡C for both the pure titanium and titanium alloy.

Keywords: Compressive strength; density; porosity; pure titanium; titanium alloy

 

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*Corresponding author; email: hamidi@eng.ukm.my