ANALYTICAL AND EXPERIMENTAL STUDY OF INVESTMENT CASTING WITH LASER STEREOLITHOGRAPHY MODELS by Wen-Long Yao This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell...

The origins of fractures in Martian boulders are unknown. Here, using Mars Exploration Rover 3D data products, we obtain orientation measurements for 1,857 cracks visible in 1,573 rocks along the Spirit traverse and find that Mars rock cracks are oriented in statistically preferred directions similar to those compiled herein for Earth rock cracks found in mid-latitude deserts. We suggest that M...

Conversion of vegetable oils and animal fats composed predominantly of triglycerides using pyrolysis type reactions represents a promising option for the production of renewable fuels and chemicals. The purpose of this article was to collect and review literature on the thermo-chemical conversion of triglyceride based materials. The literature was divided and discussed as (1) direct thermal cra...

In steel industry, without consideration of blast furnaces, reheating furnaces are classified the biggest energy consumers. The research of efficient control algorithms permitting less energy consumption has become an important issue for those furnaces. In this paper, a nonlinear Model Predictive Controller (MPC) is designed for a steel slab walking-beam reheating furnace. A numerical nonlinear...

A two-dimensional thermal elasto-plastic numerical model is developed by finite element method to analyze and compare the mechanical driving factor for heat affected zone (HAZ) liquation cracking during laser welding and hybrid laser-arc welding techniques. Calculations of transient temperatures and cooling rates are used in conjunction with solidification theory to analyze weld pool characteri...

Dalam pengoperasian furnace, uap yang dihasilkan furnace harus dijaga pada suhu 370-375oC dan tidak boleh melebihi 375oC untuk mencegah terjadinya cracking waste oil. Salah satu sistem kontrol dapat digunakan mengontrol adalah optimal dengan metode LQR (Linear Quadratic Regulator). Penerapan ini mampu mempercepat waktu keadaan mantap sistem. Performansi telah memenuhi syarat keoptimalan sebuah ...

In this work, the thermal environment inside the furnace of a dynamic mechanical analyser was investigated by putting a standard sample in distinct positions inside the furnace. Penetration experiments were carried out in order to compare the measured melting temperature of the sample with the theoretical melting temperature. The thermal gradients were investigated for three distinct modes: com...

Abstract Fe–26Si–9B alloy is a promising high temperature phase change material (HTPCM), due to its heat of fusion, small volumetric change, abundance, and low cost. Additionally, graphite has been identified as candidate for use container this alloy. In study, the feasibility using HTPCM investigated in pilot-scale. Specifically, 4–5 kg master alloys were melted crucibles an induction furnace,...

High velocity oxy-fuel (HVOF)coating have shown high resistance to corrosion in fossil energy applications and it is generally accepted that mechanical failure, e.g. cracking or spalling, ultimately will determine coating lifetime. The use of HVOF thermal spray to apply coatings is one of the most commercially viable and allows the control of various parameters including powder particle velocit...