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DataPLUS 模块提供上万种金属材料和非金属材料的腐蚀数据、焊接性能、尺寸与公差信息以及涂层信息。 点击这里了解更多。
Overview of Total Materia database 2022 年 1月 12日
Overview of Total Materia database 2022 年 1月 13日
在使用Total Materia几个月之后,以及深刻体验过所有潜在功能之后,我非常感谢你们的卓越工作和持续稳定的升级服务。 Total Materia始终是用来达成这一目的唯一工具。
M. Manfredini Bonfiglioli Industrial Gearmotors 博洛尼亚, 意大利
我们的目标很简单,就是让 Total Materia成为全球工程师在材料领域的首选一站式解决方案
Prof. Dr. Viktor Pocajt, CEOKey to Metals AG
Powder Bed Fusion (PBF) is ASTM standard technological term used to quantify well-known 3D printing techniques such as Direct Metal Laser Sintering, Electron Beam Melting, Direct Laser Melting and Selective Laser Melting. The main advantages of the PBF techniques include high precision of complex geometries, diverse application using different metal types and advantageous mechanical properties of the finished component.
Powder Bed Fusion (PBF) is the ASTM standard name for 3D printing techniques that build through a bed of powder (Direct Metal Laser Sintering, Electron Beam Melting, Direct Laser Melting and Selective Laser Melting).
Metal parts produced using PBF melting technology are free from residual stresses and internal imperfections, making them ideal for demanding applications found in the aerospace and automotive industries.
The history and categorization of PBF metal 3D printers get a bit messy and it mostly relates to the difference between sintering and melting. The different Powder Bed Fusion methods notably include:
• Selective Laser Sintering (SLS) - SLS 3D printing technology originated in the late 1980’s at the University of Texas at Austin. Over the years, this technology has experienced remarkable advances. Basically, the process uses lasers to sinter, or coalesce, powdered material layer-by-layer to create a solid structure. The final product, rendered enveloped in loose powder, is then cleaned with brushes and pressurized air. The main materials used in the SLS 3D printing process include polyamide (Nylons), Alumide (a blend of gray aluminum powder and polyamide), and rubber-like materials. Nylons are strong and durable but do feature some flexibility, making them excellent for snap fits, brackets, clips, and spring features. Designers should take the susceptibility for shrinkage and warping of thin parts into consideration during the conceptual phase.
• Selective Laser Melting (SLM), also called Direct Metal Laser Sintering (DMLS) - The same technical principle is used to produce Selective Laser Melting (SLM) and Direct Metal Laser Sintering (DMLS) parts, but is exclusively used to produce metal parts. SLM achieves a full melt of the powder so that single-component metals, such as aluminum, can be used to create light, strong spare parts and prototypes. DMLS sinters the powders and is restricted to alloys, including titanium-based alloys. These methods require added support to compensate for the high residual stress and to limit the occurrence of distortion. Applications include jewelry and dental industries, spare parts, and prototypes.
• Electron Beam Melting (EBM) - The EBM 3D printing technology attains fusion with the use of a high-energy electron beam and produces less residual stress resulting in less distortion. It uses less energy and can produce layers faster than SLS. This method is most useful in high-value industries such as aerospace and defense, motor sports, and medical prosthetics.
Sintering uses a combination of heat and pressure to make particles stick together. Melting uses high enough temperatures to cause the particles to fully melt and join together. Sintered parts have high porosity and require heat treatments to be strengthened, though they’ll never be as strong as forged metal parts; melted parts are nearly fully solid and don’t require heat treatments. In the image below you can see the difference between a sintered and melted part. The particles of the sintered part are simply touching real well but there are large gaps between them throughout the body. In contrary to the melted image on the right. The particles seen are melted and the body is a far more cohesive solid mass with no visible voids.
Figure 1 shows difference in microstructure between sintered and melted product.
When the German company EOS came up with the term DMLS, they were actually sintering and using the heat treatments afterward, but since then they’ve started using stronger lasers that do fully melt. They just hung on to DMLS term, likely because it was already popular and users don’t like having to remember a dozen different acronyms.
Another difference is that SLM works with a single metal at a time and DMLS works with metal alloys.
The industry uses both terms (SLM and DMLS), nowadays most metal 3D printing companies use a form of melting instead of sintering.
Electron Beam Melting (EBM) uses a high-power electron beam, rather than a laser, to melt the metal powder; electron beams produce more energy and higher temperatures than lasers so they can handle (and are limited to) high-temp superalloys.
Several industries rely on parts created on metal powder bed fusion 3D printers. Medical professionals and surgeons use these 3D printed metals for biocompatible implants, aerospace engineers use them to reduce the weight of aircraft, and industrial manufacturers use them for custom tooling equipment.
Metal PBF Pros
Metal PBF Cons
References 1. L. Langnau: What is the difference between powder bed fusion and ultrasonic additive manufacturing?, December 2018; 2. Introduction to 3D printing - additive processes, Accessed FEB 2020; 3. Metal 3D Printing: An Overview of the Most Common Types, Accessed FEB 2020.
Date Published: Apr-2020
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The Total Materia database contains a large number of metallography images across a large range of countries and standards.
Using the specifically designed Metallography tab in the menu bar, you can select the material of interest to you from the list of materials with metallography data included.
Metallography data can also be found through our standard quick search and will show relevant data is available through the standard Subgroup page for the material of interest.
Simply enter your material designation in to the "Material" field and select the standard of interest if known, then click "Search".
General information on microstructure can be found along with the relevant chemical composition for the material of interest.
Where available, a series of images will be provided showing a range of structural detail at various levels of magnification.
It is also possible to select different condition options from the "Select condition" drop-down to show metallography images under different process and heat treatment states.
For you’re a chance to take a test drive of the Total Materia database, we invite you to join a community of over 150,000 registered users through the Total Materia Free Demo.