Search results

Filters

  • Journals
  • Date

Search results

Number of results: 3
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

The results of investigations of the influence of the matrix grain sizes on properties of cores made by the blowing method are presented in

the hereby paper. Five kinds of matrices, differing in grain size compositions, determined by the laser diffraction method in the Analysette

22NanoTec device, were applied in investigations. Individual kinds of matrices were used for making core sands in the Cordis technology.

From these sands the shaped elements, for determining the apparent density of compacted sands and their bending strength, were made by

the blowing method. The shaped elements (cores) were made at shooting pressures being 3, 4 and 5 atn. The bending strength of samples

were determined directly after their preparation and after the storing time of 1 hour.

Go to article

Authors and Affiliations

R. Dańko
Download PDF Download RIS Download Bibtex

Abstract

Core sands for blowing processes, belong to these sands in which small amount of the applied binding material has the ability of covering

the sand matrix surface in a way which - at relatively small coating thickness - allows to achieve the high strength. Although the deciding

factor constitute, in this aspect, strength properties of a binder, its viscosity and ability to moisten the matrix surface, the essential meaning

for the strength properties of the prepared moulding sand and the mould has the packing method of differing in sizes sand grains with the

coating of the binding material deposited on their surfaces.

The knowledge of the influence of the compaction degree of grains forming the core on the total contact surface area can be the essential

information concerning the core strength.

Forecasting the strength properties of core sands, at known properties of the applied chemically hardened binder and the quartz matrix,

requires certain modifications of the existing theoretical models. They should be made more realistic with regard to assumptions

concerning grain sizes composition of quartz sands and the packing structure deciding on the active surface area of the contacts between

grains of various sizes and - in consequence - on the final strength of cores.

Go to article

Authors and Affiliations

R. Dańko

This page uses 'cookies'. Learn more