Use of Cavitation Abrasive Surface Finishing to Improve the Fatigue Properties of Additive Manufactured Titanium Alloy Ti6Al4V University of Washington

Format:

Book

Conference/Event

Author/Creator:

Sanders, Daniel, author.

Contributor:

de silva, Channa

Soyama, Hitoshi

Conference Name:

AeroTech® Digital Summit (2021-03-09 : Live Online, Pennsylvania, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2021

Summary:

Additive manufactured AM metals are attractive materials, as shape is directly formed from Computer aided design CAD data with less leading time. However, weak fatigue properties are big problem for practical applications. In order to improve fatigue life and strength, a novel mechanical surface treatment using cavitation and abrasive impact is developed. Whereas cavitation normally causes severe damage in hydro-machineries, cavitation impact is utilized for introduction of compressive residual stress into metallic materials by peening. The peening method using cavitation impact is named as "cavitation peening". Although cavitation is produced by injecting a high-speed water jet into a water-filled chamber during cavitation peening, "cavitation peening" is different from "water jet peening", in which water column impact is used. The other advantage of the proposed treatment is smoothing of the surface of AM metals. The abrasive, which is put in the chamber and accelerated by the jet, hits the surface and removes the un-melted particles. In the present paper, AM Ti6Al4V manufactured by electron beam melting EBM and direct metal laser sintering DMLS were treated by proposed cavitation abrasive surface finishing CASF, and tested by a plane bending fatigue test. The surface characteristic such as residual stress and roughness were also evaluated. The manufactured surface and the fractured surface were observed by a scanning electron microscope SEM. It was demonstrated that the fatigue strength at 10,000,000 cycles of an as-built specimens was improved from 169 ± 14 MPa to 386 ± 9 MPa for EBM and from 185 ± 9 MPa to 425 ± 9 MPa for DMLS by CASF and cavitation peening. Namely, the fatigue strength of the as-built specimen was improved 2.2 times by the proposed treatment. This work was partly supported by JSPS KAKENHI Grant Number 18KK0103 and 20H02021

Notes:

Vendor supplied data

Publisher Number:

2021-01-0024

Access Restriction:

Restricted for use by site license