A foundry notebook · turbine blades
Casting defects, superalloys, ceramic cores and shell moulds, directional and single-crystal solidification. Every entry is an open publication with full bibliographic data, a link to the source and a plain reading of what was done, what was found and what is worth checking.
SolidificationPaper
Molten metal from the seed runs into the gap and freezes as a chilled layer. With a 0.3 mm gap the casting stays single-crystal; with 1.0 mm, stray grains grow out of the layer.
Read the entryDefectsPaper
A Beijing group proposes ranking porosity tendency by two properties of the last liquid – the solid–liquid density difference and its viscosity – via Darcy's law.
DefectsPaper
MIT and ORNL derive a criterion for the onset of local remelting in the mushy zone. Its critical value is not an alloy constant – it changes along the solidification path and shifts noticeably even within a narrow composition range.
CoresPaper
Tianjin University and BIAM: with 15% kyanite and sintering at 1225 °C, the printed core's sintering shrinkage fell to 3.06% and its sag at 1540 °C to 0.82 mm.
DefectsPatent
A patent application: where freckles show up on a trial casting, thin wax rods are attached to the pattern across or along the convection flow. The segregation channels move into these ribs, which are ground off afterwards.
SolidificationPatent
An SJTU application: ceramic-fibre plates at critical levels of the mould block vertical radiation and reduce front tilt. Lower freckle and stray-grain tendency is claimed.
Shells and patternsReview
Hot water, hot air, superheated wax, polyglycols, boilerclave steam, microwaves, dissolving salt patterns – what each method means for shell cracking, wax recovery and safety.
SuperalloysPaper
VIAM ran a three-factor designed experiment on a UVNK liquid-metal-cooling furnace and obtained regression models for yield, orientation and PDAS.
SolidificationPaper
In an industrial Bridgman furnace the side of the rod next to the chill ring, where the axial gradient is highest, had a coarser PDAS than the centre. The tilt of the liquidus isotherm matters, not just G and v.
CoresPatent
A Jiangsu University patent: fused alumina with quartz and MgO on a sodium phosphate and sodium aluminate binder, claimed to dissolve in caustic or hot water in 2–4 hours.
A claimed approach, not a confirmed result. Until it is independently checked, it is an idea for a trial.
A reason to test, not a shop-floor instruction. Every entry states the scale of the work and the kind of evidence.
A hypothesis about a mechanism. Only an experiment confirms it, and we say so.
Numbers come from the source only. Every entry states what it was read from: the full text, the abstract or the patent description. About
