Analytical laser rapid prototyping application: laser sintering

Knowledge sharing by Guangdong Shunde Teamwork Model Technology Co., Ltd, whom with over 20 years rapid prototyping experience.

1 Introduction

Rapid prototyping (RP) technology is a new prototyping technology developed in the mid-1980s. At the beginning of product development, the required CAD drawings or STL files are designed, and the models are designed as actual designs before actual production. The original model of validation, product revision, functional testing, and mold development, ie prototype. RP technology integrates mechanical engineering, CAD, numerical control technology, laser technology and material science technology. It can automatically, directly, quickly and accurately transform design ideas into prototypes with certain functions or directly manufacture parts to quickly evaluate product design. , modification and functional testing, adults shorten the product development cycle: agility, suitable for any shape, highly flexible or rigid, highly integrated, etc., widely used in machinery, automotive, electronics, communications, aerospace and other fields. Since the development of RP technology, more related equipment has been developed to meet the needs of various model making.

2 e-manufacturing features based on laser sintering technology

EOS has been working on the research and development and equipment manufacturing of laser sintering rapid prototyping systems since 1989. The laser sintering technology is the core technology of E-manufacturing by EOS. E-manufacturing refers to the rapid, flexible, and low-cost manufacturing of digital files directly. This manufacturing method can now meet the different needs from mass production of individual products to mass production of individualized products, and a new combination of product design and manufacturing. The main advantages are: any shape, any time, anywhere. . The specific instructions are as follows:

(1) Any shape, that is, in any shape, can be manufactured by design. E-manufacturing based on laser sintering technology allows designers to no longer be constrained by traditional manufacturing techniques to modify the design, and stylists or industrial designers can realize their infinite creativity. For example, the profiled waterway design has become a revolutionary design to improve the heat dissipation efficiency of the mold to reduce the cooling cycle.

(2) At any time, it applies to any stage of the product life cycle. E-manufacturing is applicable to any stage of the product life cycle from pre-development to post-marketing component supply, and is not limited by professional replacement and working time, and is obtained through CAD or various design software. 3D data makes prototypes or solid parts directly and quickly.

(3) Anywhere, that applies to any industry. The e-manufacturing concept is highly competitive, making it easy to make molds and parts that are complex and expensive, and are suitable for high-tech or people's livelihood industries such as design, construction, aerospace, automotive, and robotics. At present, direct metal laser sintering (DMLS) technology presents e-manufacturing advantages, which can directly sinter copper alloy powder, aluminum silicon magnesium powder, stainless steel powder, mold steel powder, titanium alloy powder, and make mold development from rapid tooling. Advances in high-end mold making with complex waterway structures or complex geometric shapes.

3 metal powder laser rapid prototyping technology application case

The traditional manufacturing methods for titanium applications are casting, forging and machining, which are laborious and costly. Titanium is often used in parts that produce relatively small but valuable values. The laser sintering method can easily produce lightweight structural products such as hollows, which greatly improves the performance and value of the titanium component. Titanium alloy has excellent mechanical properties and corrosion resistance, small specific gravity and good biocompatibility. To date, laser titanium sintering has been used primarily in the medical and dental equipment, aerospace and automotive and fashion industries. The most commonly used material is EOS Titanium T164 (fine powder Ti6A14V alloy). In some medical cases, powders with low interstitial element content or industrial pure titanium powder are used.

Figure 1 shows a series of new dental implant screws, called TiXos, developed by Leader Italia, which can be produced using titanium raw materials in EOSINT M 270 equipment. Such screws are usually machined from solid metal and formed by melting metal powder together during laser sintering without wasting material. By controlling the laser exposure intensity, a mixed structure containing a completely dense body and a porous surface morphology is produced, so that no coating is required, and biological activity can be improved, and different types and sizes of screws can be produced in each operation as needed, and the teaching is flexible. Produce a large number of high-performance products. Laser sintering technology can be designed by computer to uniquely mimic the internal connecting holes of bone structures when manufacturing implants and related surfaces. This is not possible with traditional surface treatments.

KERRIE LUFT uses laser sintering technology to create chic footwear that is formed by the rapid prototyping of titanium to create a complex geometric heel to reflect its new art. The filament structure of the heel requires high-strength materials, and titanium is most suitable. Figure 2 shows the MA series heel made by KERRIE LUFT in London using laser titanium sintering.

Another advantage of using direct metal laser sintering technology to make molds is to improve mold efficiency for maximum productivity. This technology saves time and cost, and allows molds to be added to the mold by adding cooling water or temperature control lines. The local temperature is lowered or the temperature is reached, and the mold is cooled or warmed more rapidly to shorten the molding cycle without causing problems such as residual stress and warpage. The traditional waterway production is done by drilling. The linear and round tubular shape must avoid the relevant structure or assemble the original, which limits the waterway design. The molds based on direct metal laser sintering technology bring a wide imagination to the location and shape of the cooling water circuit or other pipeline design. The mold with a profiled waterway shown in Figure 3 requires 2 million golf souvenirs to be produced at a low unit price. The direct metal laser sintering technology is used to make the mold for only 50 hours and can increase productivity by nearly 20%.

4 Conclusion

After more than 20 years of development, RP technology has made many breakthroughs in processing methods and materials. The technology continues to grow steadily at a rate of 20%, with 1,000 to 1,500 rapid prototyping equipment sold each year. At present, there are 400 RP service organizations in the world. The expansion of this market is inseparable from the development of related equipment and the development of materials.