Reservoir heterogeneity analysis using multi-directional textural attributes from deep learning-based enhanced acoustic impedance inversion:A study from Poseidon,NW shelf Australia

Reservoir heterogeneities play a crucial role in governing reservoir performance and management.Traditionally,detailed and inter-well heterogeneity analyses are commonly performed by mapping seismic facies change in the seismic data,which is a time-intensive task.Many researchers have utilized a robust Grey-level co-occurrence matrix(GLCM)-based texture attributes to map reservoir heterogeneity.However,these attributes take seismic data as input and might not be sensitive to lateral lithology variation.To incorporate the lithology information,we have developed an innovative impedance-based texture approach using GLCM workflow by integrating 3D acoustic impedance volume(a rock propertybased attribute)obtained from a deep convolution network-based impedance inversion.Our proposed workflow is anticipated to be more sensitive toward mapping lateral changes than the conventional amplitude-based texture approach,wherein seismic data is used as input.To evaluate the improvement,we applied the proposed workflow to the full-stack 3D seismic data from the Poseidon field,NW-shelf,Australia.This study demonstrates that a better demarcation of reservoir gas sands with improved lateral continuity is achievable with the presented approach compared to the conventional approach.In addition,we assess the implication of multi-stage faulting on facies distribution for effective reservoir characterization.This study also suggests a well-bounded potential reservoir facies distribution along the parallel fault lines.Thus,the proposed approach provides an efficient strategy by integrating the impedance information with texture attributes to improve the inference on reservoir heterogeneity,which can serve as a promising tool for identifying potential reservoir zones for both production benefits and fluid storage.

Exact solution for thermal vibration of multi-directional functionally graded porous plates submerged in fluid medium

An analytical method for analyzing the thermal vibration of multi-directional functionally graded porous rectangular plates in fluid media with novel porosity patterns is developed in this study.Mechanical properties of MFG porous plates change according to the length,width,and thickness directions for various materials and the porosity distribution which can be widely applied in many fields of engineering and defence technology.Especially,new porous rules that depend on spatial coordinates and grading indexes are proposed in the present work.Applying Hamilton's principle and the refined higher-order shear deformation plate theory,the governing equation of motion of an MFG porous rectangular plate in a fluid medium(the fluid-plate system)is obtained.The fluid velocity potential is derived from the boundary conditions of the fluid-plate system and is used to compute the extra mass.The GalerkinVlasov solution is used to solve and give natural frequencies of MFG porous plates with various boundary conditions in a fluid medium.The validity and reliability of the suggested method are confirmed by comparing numerical results of the present work with those from available works in the literature.The effects of different parameters on the thermal vibration response of MFG porous rectangular plates are studied in detail.These findings demonstrate that the behavior of the structure within a liquid medium differs significantly from that within a vacuum medium.Thereby,they offer appropriate operational approaches for the structure when employed in various mediums.

PERIPHERAL FACIAL PARALYSIS TREATED BY MULTI-DIRECTIONAL NEEDLING

Objective：To search for an effective therapy in treating peripheral facial paralysis. Methods： One hundred and eight patients were randomly divided into treatment group （n = 68） and control group （n = 40）. The multi-directional needling technique was used by selecting Jiache （颊车 ST 6）, Yangbai （阳白 GB 14） and Dicang （地仓 ST 4） in the treatment group, and the traditional acupuncture technique with conventional needle selection was used in the control group. The treatment was given once daily with 10 treatments constituting a therapeutic course, and 2 courses of treatment were given in both the groups. Results： After the treatment, of the 68 and 40 cases in treatment and control groups, 56 （82.3%） and 28 （70.0%） were cured, 11 （16.2%） and 8 （20.0%） improved in clinical symptoms and signs, 1 （1.5%） and 4 （10.0%） failed, with the total effective rate being 98.5% and 90.0% respectively, and the therapeutic effect of treatment group was significantly superior to that of control group （ P 〈 0.05）. Conclusion： The multi-directional needling is an effective therapy for treating peripheral facial paralysis.

改进型超声引导下针状可视肾镜(Needle perc)钬激光碎石术治疗肾下盏结石的临床评价:与输尿管软镜对比

目的比较改进型超声引导下针状可视肾镜(Needle perc)钬激光碎石术和输尿管软镜下钬激光碎石术治疗1~2 cm肾下盏结石的效果,为临床治疗方式的选择提供参考。方法回顾性分析2022年1月—2023年5月郑州市第一人民医院收治的60例肾内单发下盏结石(最大径1~2 cm)患者的临床资料,比较行输尿管软镜钬激光碎石术的30例患者(软镜组)和改进型超声引导下Needle perc钬激光碎石术的30例患者(Needle perc组)的临床资料。结果Needle perc组较软镜组的整体住院时间[(3.00±1.25)d vs.(4.00±1.25)d]、手术时间[(44.63±5.42)min vs.(48.50±7.24)min]和住院花费[(15518±441)元vs.(16872±903)元]均较少(P<0.05)。Needle perc组术后清石率高于软镜组[93.3%(28/30)vs.50.7%(15/30),P<0.001]。术后降钙素原(PCT)上升幅度低于软镜组[(0.02±0.01)vs.(0.12±0.18),P=0.007],而并发症发生率低于软镜组[3.3%(1/30)vs.26.7%(8/30),P=0.030]。结论对于1~2 cm的肾下盏单发结石,改进型超声引导下Needle perc钬激光碎石术清石率较高、并发症发生率低,安全且有效。

Meta-analysis of Clinical Efficacy of Warm Needling Acupuncture in the Treatment of Lumbar Disc Herniation

[Objectives]To evaluate the efficacy of warm needling acupuncture in the treatment of lumbar disc herniation(LDH)by Meta-analysis.[Methods]Randomized controlled trial of warm needling acupuncture in the treatment of lumbar disc herniation published from January 2000 to December 2021 was searched by Cochrane Library,PubMed,VIP,CNKI and Wanfang.After the quality evaluation of the literature,the Meta-analysis of the literature was carried out by using Review Manager 5.3.[Results]A total of 10 studies were included,involving a total of 980 patients.The results of Meta-analysis showed that warm needling acupuncture in the treatment of lumbar disc herniation could improve the total clinical effective rate,OR=5.38,95%CI(3.40,8.49),P<0.00001;decrease the VAS score,MD=-3.33,95%CI[-4.53,-2.12],z=5.42(P<0.00001);increase the JOA score,MD=-5.63,95%CI[-8.12,-3.14];improve the dysfunction,MD=-5.63,95%CI[-8.12,-3.14],z=4.43(P<0.00001);decrease inflammatory factors,MD=-11.09,95%CI[-13.60,-8.58],z=8.65(P<0.00001).And the recurrence rate was low,OR=0.33,95%CI[0.15,0.70],z=2.86(P=0.004).[Conclusions]Warm needling acupuncture could effectively treat lumbar disc herniation and relieve pain symptoms.However,due to the general poorness of literature quality and the low quality of evidence,high-quality randomized controlled trials are still needed.

Clinical Observation of Warm Needling Acupuncture of Mongolian Medicine in the Treatment of Lumbar Disc Herniation

[Objectives]To observe the clinical efficacy of warm needling acupuncture of Mongolian medicine in the treatment of lumbar disc herniation(LDH).[Methods]120 patients with lumbar disc herniation hospitalized in Inner Mongolia International Mongolian Hospital from June 2019 to June 2022 were randomly divided into observation group(n=60)and control group(n=60).The observation group was treated with warm needling acupuncture of Mongolian medicine,and the control group was treated with common acupuncture of Mongolian medicine,with two weeks as a course of treatment.The pain visual analogue scale(VAS)and Japanese orthopaedic association(JOA)score were observed before and after treatment,and the clinical efficacy was evaluated by the changes of clinical symptoms and signs of Mongolian medicine.[Results]The cure rate of the observation group was 71.7%,which was better than that of the control group(53.3%).The difference in the cure rate between the two groups was statistically significant,X 2=4.302,P=0.038.The total markedly effective rate(cured+markedly effective)of the observation group was 90.0%,while that of the control group was 83.3%.There was no significant difference in the total markedly effective rate between the two groups,X 2=1.154,P=0.283.The total effective rate(cured+markedly effective+effective)of the observation group was 100%,while that of the control group was 95.0%.There was no significant difference in the total effective rate between the two groups,and the continuous corrected chi-square value was 1.368 and 0.242.After treatment,the degree of low back pain,lower limb pain and dyskinesia were significantly improved in the two groups,the observation group was better than the control group,and the difference was statistically significant(P<0.05).[Conclusions]The warm needling acupuncture of Mongolian medicine was effective in the treatment of lumbar disc herniation,which is worth popularizing.

History and Development of Zhuang Medicine Shallow Needling from Bone Needle,Pottery Needle,and Bronze Needle to Electroacupuncture

Zhuang medicine shallow needling has a long history and plays a significant role in Chinese medicine.With the development of medical treatment in China,there is a constant improvement in the use of needles.Bone needles have been modified to pottery needles,bronze needles,and electroacupuncture.From this long development history,there are some improvements in terms of material and technology.By analyzing and comparing the primitive and current acupuncture instruments used in China and their therapeutic effects,it can be seen that China’s medical treatment is constantly improving and will continue to improve with technology.

Assessment of Knowledge, Attitude and Practices among Healthcare Workers in a Tertiary Care Hospital on Needle Stick Injury

Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers sustain Needle stick injuries each year. This study was conducted to assess healthcare workers’ knowledge, attitude and practices regarding needle stick injury. Materials & Methods: A cross-sectional study was conducted in a Tertiary Care Hospital over the period of 3 months. The study population consisted of Intern Doctors, Post Graduate resident Doctors, Staff Nurses, laboratory technicians of Government Medical College and New Civil Hospital, Surat (n = 300). The data were collected using a self-administered questionnaire via the means of Google Forms. Questionnaire was made with prior review literature. The data obtained were entered and analysed in Microsoft Excel. Results: The prevalence of NSI in our study was 46%, with a higher prevalence among the PG residents (72%). Overall scores regarding knowledge and attitude were better in PG residents (knowledge score > 7 in 71% and Attitude Score > 7 in 68% of PG Residents). Even though the PG residents scored highest in the knowledge category, the majority of them suffered needle stick injuries as a result of poor practice scores. Among those who had NSI (n = 139/300), 70% of study participants had superficial injuries, only 9% reported the incident, 18% got medical attention within 2 hours of the incident, and 7% followed up to recheck their viral markers status. Most incidents of NSI were due to hypodermic needles while recapping needles. Conclusion: Exposure to needle stick injuries and their underreporting remains a common problem. It is imperative that healthcare workers receive regular training on the proper handling of sharp objects. We can also draw the conclusion that preventing NSIs requires putting knowledge into practice.

MXene Enhanced 3D Needled Waste Denim Felt for High‑Performance Flexible Supercapacitors

MXene,a transition metal carbide/nitride,has been prominent as an ideal electrochemical active material for supercapacitors.However,the low MXene load limits its practical applications.As environmental concerns and sustainable development become more widely recognized,it is necessary to explore a greener and cleaner technology to recycle textile by-products such as cotton.The present study proposes an effective 3D fabrication method that uses MXene to fabricate waste denim felt into ultralight and flexible supercapacitors through needling and carbonization.The 3D structure provided more sites for loading MXene onto Z-directional fiber bundles,resulting in more efficient ion exchange between the electrolyte and electrodes.Furthermore,the carbonization process removed the specific adverse groups in MXenes,further improving the specific capacitance,energy density,power density and electrical conductivity of supercapacitors.The electrodes achieve a maximum specific capacitance of 1748.5 mF cm-2 and demonstrate remarkable cycling stability maintaining more than 94%after 15,000 galvanostatic charge/discharge cycles.Besides,the obtained supercapacitors present a maximum specific capacitance of 577.5 mF cm^(-2),energy density of 80.2μWh cm^(-2)and power density of 3 mW cm^(-2),respectively.The resulting supercapacitors can be used to develop smart wearable power devices such as smartwatches,laying the foundation for a novel strategy of utilizing waste cotton in a high-quality manner.

Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on P.taeda were analyzed for various elements and properties.All soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple elements.YNC symptoms started at needle tips,then extended toward the needle base with time.First flush needles had longer portions with YNC than second flush needles did.Needles from the lower crown also had more symptoms along their length than those higher in the canopy.Symptoms were similar to those reported for Mg.In chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of P.taeda in various parent soils in Brazil.

Time-resolved characteristics of a nanosecond pulsed multi-hollow needle plate packed bed dielectric barrier discharge

In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and achieve large-volume stable discharge.The dynamic characteristics of the plasma,the generated active species,and the energy transfer mechanisms in both positive discharge(PD)and negative discharge(ND)are investigated by using fast-exposure intensified charge coupled device(ICCD)images and time-resolved optical emission spectra.The experimental results show that the discharge intensity,number of discharge channels,and discharge volume are obviously enhanced when the multi-needle electrode is replaced by a multihollow needle electrode.During a single voltage pulse period,PD mainly develops in a streamer mode,which results in a stronger discharge current,luminous intensity,and E/N compared with the diffuse mode observed in ND.In PD,as the gap between dielectric beads changes from 0 to250μm,the discharge between the dielectric bead gap changes from a partial discharge to a standing filamentary micro-discharge,which allows the plasma to leave the local area and is conducive to the propagation of surface streamers.In ND,the discharge only appears as a diffusionlike mode between the gap of dielectric beads,regardless of whether there is a discharge gap.Moreover,the generation of excited states N_(2)^(+)(B^(2)∑_(u)^(+))and N2(C^(3)Π_(u))is mainly observed in PD,which is attributed to the higher E/N in PD than that in ND.However,the generation of the OH(A^(2)∑^(+))radical in ND is higher than in PD.It is not directly dominated by E/N,but mainly by the resonant energy transfer process between metastable N_(2)(A^(3)∑_(u)^(+))and OH(X^(2)Π).Furthermore,both PD and ND demonstrate obvious energy relaxation processes of electron-to-vibration and vibration-to-vibration,and no vibration-to-rotation energy relaxation process is observed.

A Set of Acupuncture Needles in the Late Qing Dynasty Collected by George Souliéde Morant

In the early 20th century,French vice-consul George Souliéde Morant encountered acupuncture during his visit to China,and then brought it back to France.After more than a century,his collection was transported from Paris,France to Kunming,China,and later recognized as a Chinese national third-class precious cultural heritage.Currently housed in the Museum of Western Studies on Chinese Medicine at Yunnan University of Chinese Medicine,this set of instruments includes one needle holder converted from a fan-shaped holder,ten acupuncture needles,and eleven paper tags handwritten in English with names of diseases and body parts.This article attempts to present the foundational information and historical significance of this collection of this set of late Qing dynasty acupuncture instruments by reviewing the collection and related research on acupuncture instruments,consulting acupuncture professionals,measuring the detailed information of the set of instruments,and employing a method of translating and summarizing the content of the attached tags.

Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay.Positive and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were applied.Time-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)camera.The minimum delay between the camera channels could be as short as≈0.1 ns.This made it possible to study the gap breakdown process with subnanosecond resolution.It was observed that a wide-diameter streamer develops from the high-voltage pointed electrode.The ionization processes near the grounded pin electrode started when the streamer crossed half of the gap.After bridging the gap by the streamer,a diffuse discharge was formed.The development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next stage.It was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter streamer.Long thin luminous tracks were observed against the background of a discharge plasma glow.It has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

Percutaneous ultrasound-guided coaxial core needle biopsy for the diagnosis of multiple splenic lesions: A case report

BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic dilemma.Consequently,a definitive diagnosis primarily relies on his-tological results.The ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related complications.CASE SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic lesions.Gray-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic ma-sses.Abdominal contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-shaped,peripherally enhancing,hypodense lesions.Positron emission CT revealed numerous abnormal hyperglycemia foci.These imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring exclusion.To obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried out.The patient did not express any discomfort during the procedure.CONCLUSION Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue.

Needle arthroscopic-assisted repair of tibio-fibular syndesmosis acute injury:A case report

BACKGROUND Acute injuries to the tibiofibular syndesmosis,often associated with high ankle sprains or malleolar fractures,require precise diagnosis and treatment to prevent long-term complications.This case report explores the use of needle arthroscopy as a minimally invasive technique for the repair of tibiofibular syndesmosis injuries.CASE SUMMARY We report on a 40-year-old male patient who presented with a trimalleolar fracture and ankle subluxation following a high ankle sprain.Due to significant swelling and poor soft tissue quality,initial management involved external stabilization.Subsequently,needle arthroscopy was employed to assess and treat the tibiofibular syndesmosis injury.The procedure,performed under spinal anesthesia and fluoroscopic control,included nanoscopic evaluation of the ankle joint and reduction of the syndesmosis using a suture button.Follow-up assessments showed significant improvement in pain levels,range of motion,and functional scores.At 26 weeks post-procedure,the patient achieved full range of motion and pain-free status.Needle arthroscopy offers a promising alternative for the management of acute tibiofibular syndesmosis injuries,combining diagnostic and therapeutic capabilities with minimal invasiveness.CONCLUSION This technique may enhance clinical outcomes and reduce recovery times,warranting further investigation and integration into clinical practice.

Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients

Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. .

Indications for Renal Needle Biopsy and Histological Spectrum of Kidney Disease in Togo

Introduction: The frequent late-stage diagnosis of chronic kidney disease (CKD) constrains the treatment choices for nephrologists. Renal biopsy (RB) is crucial for accurately identifying renal lesions. This key nephrological procedure, however, is invasive and not without potential complications. The purpose of this study was to evaluate the indications, frequency, and histological lesion profiles of renal biopsies in Togo. Materials and Methods: We conducted a descriptive cross-sectional study encompassing all renal biopsies performed in Togo from the inception of nephrology services to the present. Data were compiled from the medical records of the patients. Results: From 2015 to 2023, 68 high-quality renal biopsies were executed in Togo. The patients had an average age of 30.6 years, with a predominance of males (69.1%). The most common indication was nephrotic syndrome, accounting for 66.2% of cases. Histologically, glomerulopathies were predominant, representing 61.8% of lesions, followed by vascular nephropathies (25%) and tubulointerstitial nephropathies (13.2%). The most frequently observed primary glomerulopathy was focal segmental glomerulosclerosis (FSGS). Gross hematuria was the sole complication, occurring in 1.4% of the cases. Conclusion: RB is an evolving practice in Togo. Glomerulopathies are the most commonly observed lesions. The histological categorization of renal lesions is vital for clinicians in their diagnostic reasoning and approach.

Observation on Therapeutic Effect of Lotus Needle Cupping Therapy for Removing Blood Stasis in Zhuang Medicine on PHN and Its Influ-ence on Inflammatory Mediators

[Objectives]To observe the clinical effect of the lotus needle cupping therapy for removing blood stasis in Zhuang medicine in treating PHNand its influence on inflammatory factors.[Methods]96 patients with PHN were randomly divided into three groups:lotus nee-dle cupping therapy group,TCM surrounding acupuncture group and gabapentin group.Venous blood and acupoint blood were collected at 0,21 and 42 d of treatment,and the expression levels of 5-HT,SP and CGRPinflammatory mediators were detected before and after treatment.The changes of VAS scores before,during and after treatment and the clinical efficacy were observed.[Results]The total effective rate of the lotus needle cupping group was 87.50%,which was better than that of the TCM acupuncture group(81.25%)and the gabapentin group(62.50%);after treatment,the VAS scores and the expression of inflammatory mediators in the three groups of patients were lower than those before treatment,and the decrease was more significant in the treatment group(P<0.05).[Conclusions]The lotus needle cupping therapy for removing blood stasis in Zhuang medicine is effective in treating PHN,and its mechanism is to reduce the release of inflammatory media-tors,reduce hyperalgesia,relieve pain and improve the quality of life of patients.

Shelton Vision pushes the needle on Al-assisted quality control

MANCHESTER,UK-Having successfully demonstrated its WebSpector automated fabric inspection system detecting faults on camouflage fabrics at speeds of up to 100metres a minute during ITMA 2023,BTMA member Shelton Vision has secured an unprecedented number of new orders in many fields of the textile industry.The company has subsequently been recruiting additional staff in order to beef up its operations to meet delivery times and to grow capacity for the ongoing increased demand.

Structure uniformity and limits of grain refinement of high purity aluminum during multi-directional forging process at room temperature

The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinement limitation with very high strains. The results show that the fine grain zone in the center of sample expands gradually with the increase of forging passes. When the forging passes reach 6, an X-shape fine grain zone is initially formed. With a further increase of the passes, this X-shape zone tends to spread the whole sample. Limitation in the structural refinement is observed with increasing strains during multi-forging process at the room temperature. The grains size in the center is refined to a certain size （110 μm as forging passes reach 12, and there is no further grain refinement in the center with increasing the forging passes to 24. However, the size of the coarse grains near the surface is continuously decreased with increasing the forging passes to 24.