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Why is Metal based Powder Bed Fusion so Complex???

The world of Additive Manufacturing is very complex. The fortune to work in the sub field of powder based metal additive manufacturing has exposed me to a multi dimensional world of process parameters, material properties, calibration of the printer, build plan and post processing. Each of the above mentioned broad categories have a fractal of parameters that makes it difficult to mathematically model a simple metal powder based additive manufacturing problem. Honestly, after a certain point of designing experiments, it becomes a brain draining process to try to understand the physical aspects that govern the process or what weights do each of the many parameters carry on the final printed sample. Parameters like hatch spacing, laser power, laser speed, type of support structures, thermal conductivity of the powder, hatch angle change with every layer, scanning pattern, build orientation, downskin thickness, laser jump speed, oxygen content in the raw material, offset to contour, numbe...
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Future of Construction

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Concrete is one of the most essential ingredients in the construction of one's dream house. It helps in maintaining the s and strength to make the structure more durable. However with the invention of 3D Printing, it is now possible to extrude large amounts of cement through an appropriately sized nozzle layer by layer. Composition of concrete can be varied in accordance with the bond strength between layers and exttudability of concrete. The nozzle should be designed such that the pumped concrete extrudes with the proper shape depending on the nozzle ending. C3DP can be achieved by various means such as extrusion screw or plunger arrangement depending on the setup of the assembly. The following images show the setup of a 4 inch stainless steel screw on the gantry of a 3D Printer. A nozzle was not used during extrusion. Note that the cracks the extruded material indicate the lack of compression of concrete within the barrel. It also indicates that the material requires certain c...
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Can 3D Printing take over the World?

3D Printing is now one of he most discussed subjects in the modern world with its field offering us untapped potential for the future manufacturing and construction applications. Its almost as if everyday you hear a new story regarding any advancement in this field. Its applications are so diverse that you can find its use in almost any major industry. Automobile?, Sanitary?, Construction? You name it. Hell you can find its use in the medical industry as well. Within a decade or probably lesser than a decade, you will notice that the  3D printed ABS/PLA/PC models of human organs have replaced the aged and tattered PVC models. It is only a matter of time after which 3d printing will be the most discussed and developed fields among the younger generation due to the immense opportunities it will provide. Please do share your views and any ideas if any related to 3d printing. 
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Never Heard of 3D Printing???

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You might probably know the approach to how an object is manufactured by Subtractive manufacturing/ CNC Machining i.e by the process of removal of material in a particular method to obtain the desired shape and size by different cutting processes using a variety of tools. These refer to the conventional cutting and milling techniques performed on CNC Machine or if you are a Luddite probably a lathe machine. On the other hand we have quite a new form of technology for the manufacture of products which is economical and efficient called 3D Printing/ Additive Manufacturing. On comparison, in 3D Printing, objects are manufactured by the addition of several layers of the material/ fused filament of very finite thickness, hence the name additive manufacturing. In three words I think 3D PRINTING IS MAGIC . Is is the art of making any object or a design we see on a screen. 3D Printing became quite some buzz in the mid 2000s although it gained attention in 2006 due to its growing dema...
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Self Energizing Brakes

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The usual drum brakes in our car are provided with a remarkable feature called 'servo' or 'self energizing' feature. It is this feature that is responsible for the smooth and flat application of brakes in automobiles. When the vehicle is moving left, in the forward direction, then the drum will rotate in the anticlockwise direction. When the brake pedal is suddenly pressed, the two brake shoes at the drum will have full contact with the drum. However, one of the brake shoes, the primary brake shoe tends to slip for a certain distance in the drum's direction. Due to this, the primary brake shoe will tend to apply a rearwards force on the secondary brake shoe at the bottom. The wheel cylinder at the top forces the piston against the top of both the brake shoes. Due to this, the secondary brake shoe experiences force on both the sides i.e the top and bottom side.  This ensures that the brakes are applied uniformly and much less effort is applied.
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Front Wheel and Rear Wheel Drive

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Before buying a car, many thoughts enter your head such as safety features, engine, transmission system, warranties, comfort, reversing sensors and cameras and most importantly the cost. In addition to this, you should also look into the drive wheel i.e whether you want a Front Wheel Drive (FWD) or a Rear Wheel Drive (RWD). The choice you make depends on your driving skills, terrain, weather and the tires used. In a FWD, the power produced by the engine is transferred to the front wheels of the vehicle whereas in a RWD, the power from the engine is transferred to the rear wheels via a drive shaft.  Transverse engines are employed in FWD where the crankshaft axis is perpendicular to the axis of the vehicle. In RWD, longitudinal engines are used where the crankshaft axis is along the length of the vehicle which increases it's weight. Majority of the cars use FWD these days while RWD is used in sports cars. Each wheel drive has it's advantages and disadvanta...
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All about Brayton

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The thermodynamics behind the functioning of the gas turbines is the Brayton cycle. This cycle consists of four processes which may be closed or open. In a closed cycle, the working fluid is circulated within the system after a complete cycle as in the case of steam turbines. In open cycle, the working fluid enters at the inlet and leaves at the exhaust of the cycle as observed in the cast of turbojets and turbofans. The cycle consists of 2 isobaric (constant pressure) and isentropic (constant entropy) processes. The following processes occur in the gas turbine:    1. Isentropic compression (1-2)    2. Isobaric addition of heat (2-3)    3. Isentropic expansion (3-4)    4. Isobaric removal of heat (4-1) Brayton cycle for P-V and T-s diagrams However, compression and expansion processes do not occur in isentropic manner, increasing the compression ratios is the most effective way to increase the output of Brayton cycle. This fig...
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