Deformation-induced phase transformation in 4H–SiC nanopillars

Chen, Bin; Wang, Jun; Zhu, Yiwei; Liao, Xiaozhou; Lu, Chunsheng; Mai, Yiu‐Wing; Ringer, Simon P.; Fang, Ke; Shen, Y.G.

doi:10.1016/j.actamat.2014.07.055

Cited by 17 publications

(12 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At 60 nm, σ max will exceed σ c resulting a possible cleavage fracture in 3C‐SiC sample (see Figure ). Additionally to find the nature of nucleation (homogeneous or heterogeneous) comparison between τ CRSS and τ th is performed by:

{normalτ}_{CRSS} = 0.31 {(][, \frac{6 P_{cr} E_{r}^{2}}{{normalπ}^{3} R^{2}})}^{1 / 3}

…”

Section: Resultsmentioning

confidence: 99%

“…Despite substantial efforts, elastic‐plastic deformation and transition behaviors of 3C‐SiC at the nanoscale are not properly understood. Recently, deformation mechanisms at nano‐scales of other polytypes which includes amorphous, 4H and 6H–SiC have been studied . Besides, this study will also help in designing of nanoscale piezo electric, resistive and biomedical devices and sensors.…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Nanoscale elastic‐plastic deformation and mechanical properties of 3C‐SiC thin film using nanoindentation

Nawaz

Islam

Mao

et al. 2018

Int J Applied Ceramic Tech

Self Cite

View full text Add to dashboard Cite

The elastic-plastic deformation of 3C-SiC thin film was investigated by a nanoindenter equipped with the Berkovich tip. Transition from pure elastic to elasticplastic deformation was evidenced at an approximate load of 0.35 mN, when loading the sample at several peak loads ranging from 0.5 to 5 mN. The indentation size effect observed in 3C-SiC and was analyzed by Nix-Gao model. In purely elastic region, the Oliver-Pharr hardness values were 44 ± 2 GPa. In contrast, indentation size effects were evidenced in 3C-SiC specimen and the average value of Oliver-Pharr hardness in the indentation size effect region was 36 ± 2 GPa. Furthermore, depth independent or intrinsic hardness extracted from Nix-Gao was estimated as H o = 26 ± 1 GPa which was also validated by proportional specimen resistance model, ie, H 1 = 28 ± 1 and H 2 = 28.5 ± 0.1 GPa.Besides, energy principle was utilized to extract Sakai Hardness as 104 GPa, which is combined elastic and elastic-plastic response. Moreover, based on energy principle, another property, ie, work of indentation was also determined to be 20 nJ/μm 3 . Similarly, elastic modulus had almost depicted stabilized value of 325 ± 8 GPa in pure elastic and elastic-plastic regions. In addition, plastic zone size was also estimated in elastic-plastic region using Johnson cavity model at pop-in and higher loads. Based on the first pop-in load at 0.35 mN, the distributions of shear and principal stresses were evaluated on various slip planes to elaborate the deformation behavior. Increase in loading rate from 100 to 400 μN/s increased critical pop-in load from 0.35 to 0.64 mN. This increase in critical popin load with increasing loading rate and values of maximum contact pressure indicates that no phase assisted transformation will occur at pop-in load. Based on theoretically calculated maximum tensile and cleavage strengths, it was affirmed that the elastic-plastic deformation occurred due to pop-in formation rather than tensile stresses. Moreover, it was also concluded on basis of Hertzian contact theory and Schmidt law that the highest possibility of slippage in 3C-SiC was along the {111} glide plane. K E Y W O R D S

show abstract

{normalτ}_{CRSS} = 0.31 {(][, \frac{6 P_{cr} E_{r}^{2}}{{normalπ}^{3} R^{2}})}^{1 / 3}

…”

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

Nanoscale elastic‐plastic deformation and mechanical properties of 3C‐SiC thin film using nanoindentation

Nawaz

Islam

Mao

et al. 2018

Int J Applied Ceramic Tech

Self Cite

View full text Add to dashboard Cite

show abstract

“…As is the case with all refractory ceramics, high-temperature mechanical behavior of bulk SiC is relatively well documented; 76-82 existing room-temperature indentation tests [83][84][85] conducted on bulk SiC single crystals and fracture tests 86,87 performed on submicrometer-scale SiC crystals, such as nanorods and nanowires, have helped determine the effects of indenter geometry, crystal size, and crystal orientation on the room-temperature mechanical properties of SiC. Recent in situ transmission and scanning electron microscopy (TEM and SEM) based uniaxial tension and compression of a and b crystalline polytypes of SiC (e.g., 3C, 4H, and 6H structures), coupled with first principles calculations and simulations, [59][60][61]87,88 helped identify the role of crystal size and defect density on the mechanical behavior in SiC and demonstrated room-temperature plasticity, a direct indication of dislocation motion in SiC. In situ microscopy experiments revealed that dislocation motion is indeed possible at room temperature in SiC, although at applied stresses considerably higher than those typically required to fracture bulk SiC crystals.…”

Section: Introductionmentioning

confidence: 99%

Nanomechanics of Refractory Transition‐Metal Carbides: A Path to Discovering Plasticity in Hard Ceramics

2015

View full text Add to dashboard Cite

Refractory carbides of transition metals (Zr, Ta, etc.), owing to a mixture of ionic, covalent, and metallic bonding, exhibit high hardness (10s of GPa), high elastic moduli (100s of GPa), good resistance to wear, ablation, and corrosion, high‐temperature mechanical strength, along with good electrical conductivities. They are attractive as high‐temperature structural components in aerospace vehicles. Although these materials are exceptionally hard, their structural applications at low temperatures have been limited because of their brittleness. The design of ceramic materials possessing both high hardness and enhanced ductility has been a long‐standing challenge. Various research studies have focused on this topic with limited success. Here, we present a brief review of our recent results obtained from direct observations of mechanical deformation during uniaxial compression of group IV and group V transition‐metal carbide (ZrC and TaC) single crystals inside a transmission electron microscope. Our studies provide new insights into the mechanical deformation mechanisms and help to identify strategies for enhancing room‐temperature plasticity in this class of materials.

show abstract

“…23−28,35−42,49−53 Third, the atomic-scale in situ results combined with MD simulations reveal that the deformation of 4H-structured NRBs comprises three distinct stages, which has not been reported before. [23][24][25][26][27][28][35][36][37][38][39]54,55 Plasticity is first governed by full dislocation activities. Subsequently, partial dislocation activities occur at regions that have undergone full dislocation gliding, leading to the 4H to FCC phase transformation.…”

Section: Resultsmentioning

confidence: 99%

Deformation-Induced Phase Transformations in Gold Nanoribbons with the 4H Phase

Kismarahardja

Wang

et al. 2022

ACS Nano

Self Cite

View full text Add to dashboard Cite

The mechanical stability of metallic nanomaterials has been intensively studied due to their unique structures and promising applications. Although extensive investigations have been carried out on the deformation behaviors of metallic nanomaterials, the atomic-scale deformation mechanism of metallic nanomaterials with unconventional hexagonal structures remains unclear because of the lack of direct experimental observation. Here, we conduct an atomic-resolution in situ tensile-straining transmission electron microscopy investigation on the deformation mechanism of gold nanoribbons with the 4H (hexagonal) phase. Our results reveal that plastic deformation in the 4H gold nanoribbons comprises three stages, in which both full and partial dislocations are involved. At the early deformation stage, plastic deformation is governed by full dislocation activities. Partial dislocations are subsequently activated in regions that have undergone full dislocation gliding, leading to phase transformation from the 4H phase to the face-centered cubic (FCC) phase. At the last stage of the deformation process, the volume fraction of the FCC phase increases, and full dislocation activities in the FCC regions also play an important role.

show abstract

Deformation-induced phase transformation in 4H–SiC nanopillars

Cited by 17 publications

References 49 publications

Nanoscale elastic‐plastic deformation and mechanical properties of 3C‐SiC thin film using nanoindentation

Nanoscale elastic‐plastic deformation and mechanical properties of 3C‐SiC thin film using nanoindentation

Nanomechanics of Refractory Transition‐Metal Carbides: A Path to Discovering Plasticity in Hard Ceramics

Deformation-Induced Phase Transformations in Gold Nanoribbons with the 4H Phase

Contact Info

Product

Resources

About