Nano-wear-induced behavior of selective laser melting commercial pure titanium

Selective Laser Melting SLM is one of the most popular three dimensional printing methods, which can be used for manufactured real elements (with high geometrical complexity) in many application, such as medicine, automotive or aerospace industries. The SLM final parts are characterized by high mechanical properties and satisfactory physicochemical properties. However, the properties of parts depend of process parameters optimization. In this paper, effects of processing parameters, such as laser power P, scanning speed SP, layer thickness t or point distance PD on defect formation and relative densities of manufactured elements are explored. For the purpose the stainless steel 316L and pure titanium Grade II are used. The process optimization were carried out according to the formula of energy density, which is delivered to the powder material. The stainless steel samples were divided into 12 groups, depends of the energy density. The titanium parts were printed at the same value of energy, and the process parameters are changed. The microscope observation and relative density measurements were carried out. Based on the obtained results, it can be confuted that the SLM parameters have a significant effect on the samples properties and the mechanism formed defect in both material are similar.

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The Influence of Hybrid Surface Modification on the Selected Properties of CP Titanium Grade II Manufactured by Selective Laser Melting

Materials ◽

10.3390/ma13122829 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2829

Author(s):

Anna Woźniak ◽

Marcin Adamiak ◽

Grzegorz Chladek ◽

Mirosław Bonek ◽

Witold Walke ◽

...

Keyword(s):

Surface Modification ◽

Selective Laser Melting ◽

Pure Titanium ◽

Microscopic Investigation ◽

The Body ◽

Laser Melting ◽

Initial State ◽

Tin Coatings ◽

Grade Ii ◽

Titanium Grade

The human body is an extremely aggressive environment in terms of corrosion. Titanium and its alloys are one of the most popular biomaterials used for implant applications due to biocompatibility. However, every element introduced into the body is treated as a foreign body. The human body’s immune response may, therefore, lead to implant rejection and the need for reoperation. For this purpose, it seems important to carry out surface modifications by applying coatings and inter alia by texturing to implants. The objective of this paper is to investigate the effect of surface treatment on the chosen properties of the pure titanium (Grade II) samples obtained by selective laser melting (SLM) processing. The samples were divided into five groups: Initial state (after polishing), after surface modification by the physical vapour deposition (PVD) method—CrN and TiN coatings were deposited on the surface of the tested material, and after laser texturing. The paper presents the results of the microscopic investigation, chemical and phase compositions, and physicochemical and electrochemical properties of the tested samples. Based on the results obtained it can be concluded that the hybrid surface modification shows significant effects on the properties of the pure titanium. The samples with the textured PVD-deposited TiN coatings were characterized by favorable physicochemical properties and were the highest performing in terms of pitting corrosion resistance.

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Thermal behavior during selective laser melting of commercially pure titanium powder: Numerical simulation and experimental study

Additive Manufacturing ◽

10.1016/j.addma.2014.09.001 ◽

2014 ◽

Vol 1-4 ◽

pp. 99-109 ◽

Cited By ~ 74

Author(s):

Yali Li ◽

Dongdong Gu

Keyword(s):

Numerical Simulation ◽

Experimental Study ◽

Thermal Behavior ◽

Selective Laser Melting ◽

Titanium Powder ◽

Pure Titanium ◽

Commercially Pure Titanium ◽

Laser Melting ◽

Commercially Pure

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Fatigue Crack Growth Rates and Tensile Strength of Titanium Produced by Means of Selective Laser Melting

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.627.305 ◽

2014 ◽

Vol 627 ◽

pp. 305-308 ◽

Cited By ~ 4

Author(s):

Tomasz Brynk ◽

Barbara Romelczyk ◽

Zbigniew Pakiela ◽

Tomasz Kurzynowski ◽

Edward Chlebus

Keyword(s):

Mechanical Properties ◽

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Selective Laser Melting ◽

Pure Titanium ◽

Tensile Tests ◽

Image Correlation ◽

Laser Melting ◽

Full Field

Mini-samples technique was utilized to determine mechanical properties of technically pure titanium produced by means of selective laser melting (SLM). Full-field digital image correlation (DIC) measurements and inverse method were applied for crack tip position and stress intensity factors calculations in the case of fatigue crack growth rate tests. DIC was also used for strain measurement during tensile tests on sub sized samples. There was studied the influence of samples orientation on the mechanical properties of mini-samples. Samples were cut out from rectangular cubes and were oriented with 0°, 45° or 90° angle to the direction of laser beam travel. There were also tested samples directly produced via SLM. Additionally microstructure observations were performed to verify the quality of SLM processed materials and explain mechanical properties variations.

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Densification behavior, microstructure evolution, and wear performance of selective laser melting processed commercially pure titanium

Acta Materialia ◽

10.1016/j.actamat.2012.04.006 ◽

2012 ◽

Vol 60 (9) ◽

pp. 3849-3860 ◽

Cited By ~ 486

Author(s):

Dongdong Gu ◽

Yves-Christian Hagedorn ◽

Wilhelm Meiners ◽

Guangbin Meng ◽

Rui João Santos Batista ◽

...

Keyword(s):

Selective Laser Melting ◽

Microstructure Evolution ◽

Pure Titanium ◽

Densification Behavior ◽

Commercially Pure Titanium ◽

Laser Melting ◽

Wear Performance ◽

Commercially Pure

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Pure Titanium Fabrication with Spatter-less Selective Laser Melting in Vacuum

Results in Optics ◽

10.1016/j.rio.2021.100184 ◽

2021 ◽

pp. 100184

Author(s):

Yuji Sato ◽

Yuta Mizuguchi ◽

Keisuke Takenaka ◽

Norio Yoshida ◽

Sasitorn Srisawadi ◽

...

Keyword(s):

Selective Laser Melting ◽

Pure Titanium ◽

Laser Melting

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The effect of hatch angle rotation on parts manufactured using selective laser melting

Rapid Prototyping Journal ◽

10.1108/rpj-06-2017-0111 ◽

2019 ◽

Vol 25 (2) ◽

pp. 289-298 ◽

Cited By ~ 17

Author(s):

Joseph Henry Robinson ◽

Ian Robert Thomas Ashton ◽

Eric Jones ◽

Peter Fox ◽

Chris Sutcliffe

Keyword(s):

Residual Stress ◽

Surface Roughness ◽

Selective Laser Melting ◽

Pure Titanium ◽

Commercially Pure Titanium ◽

Laser Melting ◽

Content Type ◽

Axial Tensile ◽

Effects Of Rotation ◽

Scanning Strategies

Purpose This paper aims to present an investigation into the variation of scan vector hatch rotation strategies in selective laser melting (SLM), focussing on how it effects density, surface roughness, tensile strength and residual stress. Design/methodology/approach First the optimum angle of hatch vector rotation is proposed by analysing the effect of different increment angles on distribution of scan vectors. Sectioning methods are then used to determine the effect that the chosen strategies have on the density of the parts. The top surface roughness was analysed using optical metrology, and the tensile properties were determined using uni-axial tensile testing. Finally, a novel multi-support deflection geometry was used to quantify the effects of rotation angles on residual stress. Findings The results of this research showed that the hatch rotation angle had little effect on the density, top surface roughness and strength of the parts. The greatest residual stress deflection was measured parallel to unidirectional scan vectors. The use of hatch rotations other than alternating 90° showed little benefit in lowering the magnitude of residual stresses. However, the use of rotation angles with a good suitability measure distributes stresses in all directions more evenly for certain part geometries. Research limitations/implications All samples produced in this work were made from commercially pure titanium, therefore care must be taken when applying these results to other materials. Originality/value This paper serves to increase the understanding of SLM scanning strategies and their effect on the properties of the material.

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