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PLASMA SPRAYED Ti AND HA COATINGS: A COMPARATIVE STUDY BETWEEN APS AND VPS

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 339-344页

作者： x.B.Zheng H.Ji J.Q.huang C.x.Ding ShanghaiInstituteofCeramics TheChineseAcademyofSciencesShanghai200050China

Titanium (Ti) and hydroxyapatite (HA) coatings have been prepared via air (APS) and vacuum plasma spraying (VPS), and then their composition, structure, bonding strength and bioactivity were examined. The results obtained reveal that in APS process many of Ti were oxidized, but in VPS the oxidization was avoided. VPS T i coating possesses better bonding condition than APS Ti coating. As for HA coat ing, higher crystallinity has been obtained while the coating was deposited by V PS as compared with APS. The simulated body fluid (SBF) tests show that both of APS and VPS HA coatings possess good bioactivity. As compared with APS, VPS is r ecommended as a better method to deposit Ti and HA coatings that can be applied as hard tissue replacement implants.

关键词： vacuum plasma spray Ti HA biocoating

Strong and ductile Mg alloys developed by dislocation engineering

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Journal of Materials Science & Technology 2019年第3期35卷 394-395页

作者： M.Wang B.B.He M.x.huang Department of Mechanical Engineering The University of Hong Kong Shenzhen Institute of Research and Innovation The University of Hong Kong

Dislocation engineering concept has been successfully employed to tackle the strength-ductility trade-off in steels, resulting in the development of high-strength high-ductility deformed and partitioned(D&P)steel. The present perspective proposes to employ such dislocation engineering concept to develop strong and ductile magnesium(Mg) alloys. High density of dislocations could be generated at appropriate temperature and retained in the Mg alloy after quenching to room temperature. Those dislocations inherited from the warm deformation could provide dislocation sources when the Mg alloy is deformed at room temperature, resulting in good ductility. The high dislocation density generated at warm deformation provides dislocation forest hardening, leading to improved yield strength of Mg alloy.

关键词： Dislocation engineering Mg alloys Warm rolling Strength and ductility

Mechanical Properties of Wood from Transgenic Poplar Trees with Modified Lignification

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材料科学与工程学报 2000年第Z2期20卷 789-796页

作者： x.huang Centre for Biomimetics Earley Gate TOB1Reading University Reading RG6 6AT UK

Double cantilever beam (DCB) and instrumented microtome cutting (IMC) tests were carried out in testing wood fracture properties of control and various transgenic poplar plants. The results show that control plants have higher work of fracture (WF) than most transgenic plants. The air-dry materials have higher WF than wet ones and latewood is higher than earlywood. Also, samples from parts of the trunk above stye points usually have higher WF than those from below. The comparison between DCB tests and IMC studies show that, the WF obtained from DCB is higher than the cutting work measured by IMC. Scanning electronic microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to study specimens'fracture surfaces and structure. Though in all samples fracture occurred between the middle lamella and S1layers, between S1 and S2 layers, as well as within S2 layers, there are more transwall fractures in control *** are also differences in cell wall area fraction among these materials.

关键词： GM poplar plants wood lignin double cantilever beam mechanical properties

Comparing hydrogen embrittlement behaviors of two press hardening steels:2 GPa vs.1.5 GPa grade

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Journal of Materials Science & Technology 2022年第29期124卷 109-115页

作者： Z.H.Cao B.N.Zhang M.x.huang Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina

*** The pursuit of advanced high-strength steels(AHSS)has been rising for the automobile industry to build lightweight and fuelefficient vehicles without compromising crashworthiness[1,2].The group of press hardening steels(PHS)is an excellent candidate that comprises high strength,high toughness,and good formability,which are optimal to build intrusion resistant components such as(ⅰ)A/B-pillar reinforcements,(ⅱ)bumper and door beams.

关键词： strength toughness steels

On Temperature and Strain Rate Dependent Strain Localization Behavior in Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Alloy

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Journal of Materials Science & Technology 2013年第3期29卷 273-278页

作者： B.Zhang L.M.Lei x.L.Jiang Z.M.Song x.huang G.P.Zhang Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern University Titanium Alloys Laboratory Beijing Institute of Aeronautical Materials AVIC commercial Aircraft Engine Co. Ltd. Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Deformation behaviors of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloys with α/β lamellar structure were investigated systematically at different temperatures from room temperature to 950 ~C and different strain rates. Results reveal that when the deformation temperature is higher than a critical temperature of 600℃, an evident transition of deformation behavior from localized shear banding to α/β lamella kinking, flow softening and temperature/strain rate-dependent peak flow stress occurred in the alloy. The critical conditions for the occurrence of internal cracking and strain localization behavior associated with temperature and strain rate were determined.

关键词： Titanium alloy Hot working Temperature Strain rate Shear band

Gastroesophageal reflux: the features in elderlypatients

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World Journal of Gastroenterology 1999年第5期5卷 421-423页

作者： huang x Zhu HM Deng CZ Porro GB Sangaletti O Pace F Shenzhen Peoples Hosp Dept Gastroenterol Shenzhen 518001 Guangdong Prov Peoples R China Univ Milan Gastrointestinal Unit Milan Italy

AIM To compare the features ofgastroesophageal reflux disease between elderlyand younger *** Twenty-four hour pH-monitoring andendoscopy were P6rformed for the 66 elderlypatients with typical gastroesophageaI refluxsymptoms, and the results were compared with112 symptomatic younger *** The results of 24-h pH-monitoringand endoscopy showed that the elderly patientshad pathological reflux and reflux esophagitismore frequently than the younger patients.P6rcentage time with pHx esophagitis was 32.5% in 24 hours,as compared with 12.9% in the younger patientswith reflux esophagitis (P x esophagitis have longerP6riOds of acid reflux in both upright and Supinepositions than the younger patients. Endoscopyshowed that 20 .8% of elderIy patients had grade Ⅲ / Ⅳ esophagitis, whereas only 3.4% ofyounger patients had grade Ⅲ/ Ⅳ esophagitis(P x and esophageal *** incompetence of lower esophageal sphincter and the presence of hiataI hernia may beimportant factors leading to the difference in incidence and severity of reflux esophagitisbetween elderly and younger patients.

关键词： gastroesophageal reflux esophagitis hiatal hernia

Pathogenetic factors affecting gastroesophageal refluxin patients with esophagitis and concomitant duodenal ulcer:a multivariate analysis

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World Journal of Gastroenterology 1998年第2期4卷 61-65页

作者： Zhu, HM huang, x Deng, CZ Porro, GP Pace, F Sangaletti, O Jinan Univ Coll Med Affiliated Hosp 2 Dept Gastroenterol Shenzhen 518001 Guangdong Peoples R China Milan Univ Hosp Div Gastroenterol Milan Italy

AIM To assess the relationship between gastric acid output (GAO) and both pattern of gastroesophageal reflux (GER) and esophageal lesions, and to evaluate the role of GAO and other potential pathogenetic factors in the development of esophagitis. METHODS Gastric acid secretory testing and 24 h intraesophageal pH monitoring were performed in 31 patients with esophagitis and concomitant duodenal ulcer (E+DU) and compared with those of 72 patients with esophagitis (E) alone. RESULTS The GAO in patients with E+DU was significantly higher than in patients with E ( P 0 05). A multiple regression analysis with stepwise deletion showed that the pre sence of hiatal hernia (HH), GER in upright position and age appeared to correlate significantly with the presence of esophagitis. CONCLUSIONS No parallel relationship between GAO and severity of GER or esophageal lesions exists in patients with E+DU, and that GAO is not a major pathogenetic factor in GER disease.

关键词： esophagitis/etiology gastric acid/secretion duodenal ulcer/etiology gastroesophageal reflux/etiology hydrogen ion concentration multivariate analysis

Strain rate sensitivity of a 1.5 GPa nanotwinned steel

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Journal of Iron and Steel Research International 2021年第11期28卷 1352-1356页

作者： R.D.Liu Y.Z.Li L.Lin C.P.huang Z.H.Cao M.x.huang Iron and Steel Research Institute Ansteel GroupAnshan 114021LiaoningChina Department of Mechanical Engineering The University of Hong KongHong Kong 999077China

Two distinct regimes of strain rate sensitivity on yield strength are found in a high-strength nantwinned *** yield strength increases from 1410 to 1776 MPa when the strain rate increases from 10–3 to 1400 *** is proposed from the measured small activation volume that the yielding of the nanotwinned steel at higher strain rates is governed by the dislocation bowing out from the carbon *** lower strain rates,however,the yielding is controlled by the continuous re-pinning of dislocations due to the fast diffused carbon atoms,which leads to the relative insensitivity of yield strength to the strain rate.

关键词： Nanotwinned steel Strain rate sensitivity Hokinson tensile bar Twinning Twinning-induced plasticity steel

Microstructure Dependent Fatigue Cracking Resistance of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Alloy

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Journal of Materials Science & Technology 2012年第7期28卷 614-621页

作者： Z.M. Song L.M. Lei B. Zhang x. huang G.R Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China AVIC Commercial Aircraft Engine Co. Ltd. Shanghai 200241 China Titanium Alloys Laboratory Beijing Institute of Aeronautical Materials Beijing 100095 China Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education School of Materials and MetallurgyNortheastern University Shenyang 110819 China

Fatigue cracking behavior from a notch was investigated at room temperature for ***-3.5Mo-1.5Zr- 0.3Si （TClI） alloys with four different microstructures obtained at different cooling rates from the β transus temperature. It was found that the alloy with lamellar structures consisting of α/β lamellae or acicular α＇ martensite laths had a higher fatigue crack initiation threshold from the notch, while the bimodal structure with coarse a grain had a lower fatigue cracking resistance. The alloy with α/β lamellar structure showed a higher fatigue crack growth resistance. The length scales of the microstructures were characterized to correlate with fatigue cracking behavior. Fatigue cracking mechanism related to microstructures was discussed.

关键词： Ti alloy Fatigue crack initiation Crack propagation Microstructure