Replies to post #5830 on Arcam AB fka AMAVF

[charlie T colton]

Print That Part - 316L SS

"316L stainless steel is our first target alloy,"

I knew I had seen this before but had trouble locating it.

Additive manufacturing of metallic components by selective electron beam melting — a review - C. Körner

To cite this article: C. Körner (2016) Additive manufacturing of metallic components by selective electron beam melting — a review, International Materials Reviews, 61:5, 361-377, DOI:10.1080/09506608.2016.1176289

On pages 367 and 368:

Pure iron and steel

From a historical viewpoint, the processing of large and voluminous steel parts was the initial motivation to use an electron beam as energy source. Thus, at the beginning of commercialisation, Arcam’s advertising strategy was based on the high power of the electron beam able to consolidate a large volume of steel per hour. Using SEBM for production of tool steel, injection mould inserts were considered as a promising field of application. Nevertheless, the focus completely changed during the last decade and Arcam’s focus is now on titanium and titanium alloys; steel is now hardly a topic.

Altogether, the literature on SEBM of iron and steel is rather scarce. The microstructure and properties of pure iron processed by SEBM are described by Murr et al. 48 In an initial study Cormier et al. 52 presented a microstructural analysis of H13 tool steel produced via SEBM. The parts exhibited full interlayer bonding with virtually no porosity. Due to the high cooling rates, the as-built material was martensite with a hardness of 48 – 50 HRC. In Refs. 50 and 51 an Arcam SEBM H13 insert with complex cooling geometries is compared against traditionally cooled inserts. The improved cooling rates shown by SEBM inserts over conventionally cooled core inserts offer improvements with respect to the productivity and dimensional accuracy.

The formability of 316L stainless steel by SEBM was first investigated by Qi et al. 49 Gas atomised powder with particle sizes of 70 – 100 and 40 – 63 µm and water atomised powder with particle sizes of 10 – 40 and 40 – 63 µm were investigated. Generally, the water atomised powder shows a stronger tendency to balling than gas atomised powder. The microstructure is found to be fine and compact with metallurgical bonding between layers. The latest publication from the same group 14 addresses the influence of the scanning strategy on densi fication and the surface roughness. Uniform microstructures with densities of about 99.96 % can be reached. Mechanical properties are not reported.


The referenced publication in Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture - Direct metal part forming of 316L stainless steel powder by electron beam selective melting - H B Qi, Y N Yan, F Lin, W He, R J Zhang - First Published November 1, 2006

Abstract

Electron beam selective melting (EBSM) is a new type of rapid manufacturing of direct metal fabrication technology, which combines electron beam machining with rapid prototyping. It makes use of some advantages of an electron beam, such as high energy density, high absorption rate, and vacuum environment. In this study, direct metal part forming of gas and water-atomized 316L stainless steel powder were researched in detail.







I'll try and access the full document by H B Qi, Y N Yan, F Lin, W He, R J Zhang.