To gain a better understanding and control of the Selective Laser Sintering (SLS) process, more fundamental and modeling work is needed. A simple analytical ray-tracing model has been developed to simulate the energy absorption and penetration in SLS. The model is applied to FeCu and WC-Co powder mixtures, irradiated by Nd-YAG or CO2 laser. It gives an evaluation of the total energy incoupling ...

Polycrystalline samples of Lead free (K0.5Na0.5)1−x(Li)x(Sb)x(Nb)1−xO3 ceramics with nominal compositions (x = 0.040 to 0.060) have been prepared by high temperature solid state reaction technique. X-ray diffraction (XRD) pattern shows that the crystal structure transforms from orthorhombic to tetragonal as Li and Sb content increases. Normal sintering process yield compounds with density ~98.2...

Hydroxyapatite (Ca10(PO4)6(OH)2) (HAp) is a very attractive material for human tissue implantation, beacuse it makes up ~69% of the weight of bone [1]. Unfortunately HAp posses low mechanical properties (strength, fracture toughness), which is a barrier to its applications in load-bearing situations [2]. The mechanical properties of HAp composites, is based on the synthesis of composites and th...

The Sintering behavior and kinetic evaluation of the bio-ceramics from bovine bone are investigated by stepwise isothermal dilatometry (SID), X-ray diffraction (XRD) and scanning electron microscope (SEM). The isothermal shrinkage data obtained from SID could be well analyzed to get kinetic parameters according to the empirical rate equation developed by Makipirtti-Meng, dY/dt = nk(T)Y(1-Y)[Y/(...

A two stage process including a sintering under a cyclic loading is proposed as an alternative fabrication method of dense FeAl intermetallics from elemental powder mixtures. The first stage (pre-sintering) is conducted at two temperature values (620 °C and 670 °C, respectively) under a static and a cyclic loading with a frequency of 20, 40 and 60 Hz. The second one includes a pressureless sint...

The room-temperature magnetic properties of ball-milled strontium hexaferrite particles consolidated by spark-plasma sintering are strongly influenced by the milling time. Scanning electron microscopy revealed the ball-milled SrFe12O19 particles to have sizes varying over several hundred nanometers. X-Ray powder-diffraction studies performed on the ball-milled particles before sintering clearly...

With more and more materials used in the Selective Laser Sintering (SLS) process, it is becoming necessary to use a database to manage the process efficiently. In this paper, a relational database for the SLS process is described. The database includes powdered material data, sintering parameters, machine characteristics, mechanical properties and surface quality of prototypes. Use of this data...

Mold Decomposed injection sculpturing (Mold DIS) process which integrates injection and sculpturing in layered manufacture is a novel rapid prototyping technique. In this paper a wax mold is fabricated through DIS process, the 316L stainless steel slurry is then cast into the mold. After curing and drying, the wax mold is melted and the green part is obtained. The purpose of this paper is to st...

Scale up of microwave sintering for high temperature stable non-oxide ceramics, such as SiC, Si3N4, and dispersion ceramics, like SiC-MoSi2 is still difficult, mainly because of lack of an affordable equipment. For air atmosphere sintering different furnaces were developed, like e.g., gas-microwave hybrid heated tunnel kilns [1] or microwave sintering using an adiabatic casket in tunnel kilns [...