BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to the field of additive manufacturing, and more particularly, to additive manufacturing using polymer materials.

2. Discussion of Related Art

Historically, prototype development and customized manufacturing has been performed by traditional methods using metal extrusion, computer-controlled machining and manual modeling techniques, in which blocks of material are carved or milled into specific objects. These subtractive manufacturing methodologies have numerous limitations. They often require specialist technicians and can be time—and labor intensive. The time intensity of traditional modeling can leave little room for design errors or subsequent redesign without meaningfully affecting a product's time-to-market and development cost. As a result, prototypes have been created only at selected milestones late in the design process, which prevents designers from truly visualizing and verifying the design of an object in the preliminary design stage. The inability to iterate a design rapidly hinders collaboration among design team members and other stakeholders and reduces the ability to optimize a design, as time-to-market and optimization become necessary trade-offs in the design process.

Additive manufacturing (“AM”) addresses the inherent limitations of traditional modeling technologies through its combination of functionality, quality, and ease of use, speed and cost. AM is significantly more efficient and cost effective than traditional model-making techniques for use across the design process, from concept modeling and design review and validation, to fit and function prototyping, pattern making and tooling, to direct manufacturing of repeatable, cost-effective parts, short-run parts and customized end products.

Introducing 3D modeling earlier in the design process to evaluate fit, form and function can result in faster time-to-market and lower product development costs. For customized manufacturing, 3D printers eliminate the need for complex manufacturing set-ups and reduce the cost and lead-time associated with conventional tooling. The first commercial 3D printers were introduced in the early 1990s, and since the early 2000s, 3D printing technology has evolved significantly in terms of price, variety and quality of materials, accuracy, ability to create complex objects, ease of use and suitability for office environments. 3D printing is already replacing traditional prototype development methodologies across various industries such as architecture, automotive, aerospace and defense, electronics, medical, footwear, toys, educational institutions, government and entertainment, underscoring its potential suitability for an even broader range of industries.

3D printing has created new applications for model-making in certain new market categories, such as: education, where institutions are increasingly incorporating 3D printing into their engineering and design course programs; dental and orthodontic applications, where 3D printed models are being used as replacements for traditional stone models, implants and surgical guides and for crowns and bridges for casting; Furthermore, 3D printing is being used in many industries for the direct digital manufacturing of end-use parts.

Carneiro et al. 2015, Fused deposition modeling with polypropylene, Materials & Design 83:768-776 discuss the suitability of polypropylene (PP) for used in fused deposition modeling (FDM)-based 3D printing.

SUMMARY OF THE INVENTION

The following is a simplified summary providing an initial understanding of the invention. The summary does not necessarily identify key elements nor limit the scope of the invention, but merely serves as an introduction to the following description.

One aspect of the present invention provides a method of additive manufacturing, the method comprising: receiving, continuously, solid polymer material in form of at least one strand or a plurality of particles, heating a surface of the continuously received solid polymer material peripherally to liquefy the surface, using specified heating-related parameters which are selected to maintain a central volume of the continuously received solid polymer material in a solid state, liquefying a surface of a polymer substrate, and attaching the peripherally heated surface of the continuously received solid polymer material to the liquefied surface of the polymer substrate, wherein the attachment to the polymer substrate is achieved by a re-solidification of the liquefied surface to yield monolithic attachment.

These, additional, and/or other aspects and/or advantages of the present invention are set forth in the detailed description which follows; possibly inferable from the detailed description; and/or learnable by practice of the present invention.

