Material Type  

 학위논문

 

0016931302

Date and Time of Latest Transaction  

20240214095957

ISBN  

9798380622783

DDC  

539.76

Author  

Stevenson, Sarah Rachelle.

Title/Author  

Low Energy Helium Ion Implantation and Application of a High Energy Ion Implantation Tool to Comprehensively Investigate High Helium Dose Effects - [electronic resource]

Publish Info  

[S.l.] : University of California, Berkeley., 2022

Publish Info  

Ann Arbor : ProQuest Dissertations & Theses, 2022

Material Info  

1 online resource(143 p.)

General Note  

Source: Dissertations Abstracts International, Volume: 85-04, Section: B.

General Note  

Advisor: Hosemann, Peter.

학위논문주기  

Thesis (Ph.D.)--University of California, Berkeley, 2022.

Restrictions on Access Note  

This item must not be sold to any third party vendors.

Restrictions on Access Note  

This item must not be sold to any third party vendors.

Restrictions on Access Note  

This item must not be sold to any third party vendors.

Abstracts/Etc  

요약Ion beam implantations are widely performed to understand the effects of radiation damage such as He bubbles on nuclear structural materials. This work investigates near-surface changes caused by low energy ion implantations, as well as deep ion implantations leading to bulk-property changes.The near-surface interactions of low energy (25-60 keV) He ions with Ti and Cu targets were investigated by atomic force microscopy (AFM), nanoindentation, Transmission Electron Microscopy (TEM), and Positron Annihilation Spectroscopy (PAS). AFM showed a linear increase in swelling with respect to dose for all materials, and blistering onset doses of 5 x 1017 ions/cm2 , 8 x 1017 ions/cm2 , and 1 x 1018 ions/cm2 for Ti(0001), Ti(1010), and Cu(100), respectively. Cavities on the order of 287 nm diameter were observed in Cu, and surface blisters formed from the intersection of these large cavities. He bubbles observed in Ti were around 1 nm diameter, and surface blisters formed from inter-bubble fracture. PAS showed an increase in defect concentration with respect to depth and dose, agreeing well with AFM and TEM results. An additional PAS measurement determined that shock loading can lead to a decrease in vacancy concentration in a pre-implanted material.To fill the gap between widely available low energy ion implantations and difficult-to-achieve bulk implantations, this work aimed to establish the use of the 88-Inch Cyclotron for nuclear materials studies. Four HT-9 SS-J-geometry tensile specimens were irradiated with high energy (19-25 MeV) deuterons at the 88-Inch Cyclotron to doses of approximately 0.2 dpa prior to small scale tensile testing. The results from this study showed irradiation hardening characterized by black dot irradiation defects, and the tensile test results were in agreement with the available data. To support future deep ion implantation campaigns, a novel ion beam degrader capable of uniformly implanting bulk-scale materials with He ions was designed.

Subject Added Entry-Topical Term  

Nuclear engineering.

Subject Added Entry-Topical Term  

Materials science.

Index Term-Uncontrolled  

Helium effects

Index Term-Uncontrolled  

Ion implantations

Index Term-Uncontrolled  

Nuclear materials

Index Term-Uncontrolled  

Radiation damage

Index Term-Uncontrolled  

Vacancy concentration

Added Entry-Corporate Name  

University of California, Berkeley Nuclear Engineering

Host Item Entry  

Dissertations Abstracts International. 85-04B.

Host Item Entry  

Dissertation Abstract International

Electronic Location and Access  

로그인을 한후 보실 수 있는 자료입니다.

소장사항  

202402 2024

Control Number  

joongbu:641489