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The purpose of this study is to analyse the problem of high binder content in sand mould and to solve it. Meanwhile, to increase build speed, especially for heavy casting’s sand mould with a high value in layer height, such as 2 mm in construction instead of the industry standard of 0.3 mm, line forming for three-dimensional (3D) sand mould printing is researched.

Brief introduction of 3D sand mould printing and key issues are given first. Then, this paper quantitatively analyses binder content in sand mould. Finally, to acquire sand mould with appropriate binder content and high build speed, line forming combining traditional furan no-bake sand manufacture technique is researched, as well as relevant feasible schemes and current progress.

The study shows that compared with traditional technique, binder content in sand mould produced by available 3D printing technique is too high, bad for sand mould’s properties and quality of castings, while line forming brings guaranteed binder content and improved build speed.

More experiments are needed to demonstrate quantitative analysis of binder content and to obtain flowability of moist sand, detailed structure design of nozzle and practical build speed, as well as methods of circulation of materials considering solidification time.

Line forming with higher build speed and suitable binder content means excellent properties of sand mould and castings as well, bringing obvious implication for moulds industries and manufacturing industry.

This new method could increase build speed and meanwhile guarantee binder content. Thus, its application prospect is promising.

The purpose of this paper is to review available technologies, analyse their features, propose a new approach of 3D sand mould printing based on line forming, introduce the manufacturing principle and show advantages of this approach, especially for larger parts with large Z steps in the build, such as 2 mm stepwise.

This paper introduces 3D sand mould printing, compares and analyses technological process and existing fabrication approaches among available technologies first. Then, a new approach of 3D sand mould printing is proposed to improve build speed. In addition, the proposed system will be analysed or benchmarked against existing systems.

A new approach based on line forming of sand mould printing is put forward by reviewing and analysing available technologies, to improve build speed from the aspect of basic moulding movement instead of optimization of moulding methods and process parameters. The theoretical calculation and analysis shows that build speed can be improved greatly, and it is more suitable for the manufacture of large-scale casting’s sand mould when considering dimensional accuracy and printing error, as well as uniformity of each layer.

The specific implement scheme of line forming and nozzle’s specific structure of this new approach need further study.

Much higher build speed of 3D sand mould printing with new approach brings evident implication for moulds companies and manufacturing industry, having a far-reaching influence on the development of national economy.

This paper reviews available technologies and presents a new approach of 3D sand mould printing for the first time. Analysis of the new approach shows that this new method of sand mould printing can boost build speed greatly. So, its application prospect is great.

This paper aims to investigate the circulation of moist silica sand to provide appropriate feeding modes and references for designing the coating device when printing sand mold with line-forming.

First, this paper briefly introduces sand mold printing with line-forming and the circulation problem brought by moist silica sand. The outlet may be choked due to poor flowability and solidification characteristic, resulting in poor dimensional tolerance and even production failure. Then, based on circulation modeling, a series of feeding modes is proposed to guarantee adequate feeding, avoid solidification and ensure successful fabrication. Finally, the GUI of control software is developed, including slicing, path planning and the function of virtual printing.

Several feeding modes of moist silica sand are put forward to avoid the choke.

The authors will further investigate the flowability of furan no-bake sand based on experiments.

This paper is going to provide references for the novel design of nozzle, prototype and sand mold printing, influencing significantly on mold manufacturing and the casting industry. This research applies equally to equipment having the circulation of high moist particles with solidification features.

The purpose of this paper is to investigate the friction and wear performance of pure polycarbonate (PC) and 5-30 per cent wollastonite-filled (by weight) PC were comparatively evaluated under dry sliding conditions. Wear tests were carried out at room temperature under the loads of 5-20 N and at the sliding speeds of 0.5-1.5 m/s.

The microstructures of the wollastonite, pure PC and composites were examined by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis. The friction and wear tests were realized using a pin-on-disk arrangement against the hardened AISI 4140 steel.

The result of this study indicated that the coefficients of friction wear rate of the materials were significantly influenced by an increase in wollastonite content. The friction coefficient of the PC was getting decreased from 0.457 to 0.198 with an increase in wollastonite content, depending on applied loads and sliding speeds. On the other hand, the results showed that the wear rates of pure PC and wollastonite-filled PCs decreased with an increase in loads. The wear rate of the PC decreased from 1.2 × 10−6 to 8.7 × 10−6 mm3/m with an increase in wollastonite content, depending on applied loads.

There are many reports which deal with the friction and wear performance of the polymers and polymer composites. However, the effect of wollastonite effect on tribological performance of PC has up to now not been extensively researched.