Deep learning-based recognition of stained tongue coating images

Objective To build a dataset encompassing a large number of stained tongue coating images and process it using deep learning to automatically recognize stained tongue coating images.Methods A total of 1001 images of stained tongue coating from healthy students at Hunan University of Chinese Medicine and 1007 images of pathological(non-stained)tongue coat-ing from hospitalized patients at The First Hospital of Hunan University of Chinese Medicine withlungcancer;diabetes;andhypertensionwerecollected.Thetongueimageswererandomi-zed into the training;validation;and testing datasets in a 7:2:1 ratio.A deep learning model was constructed using the ResNet50 for recognizing stained tongue coating in the training and validation datasets.The training period was 90 epochs.The model’s performance was evaluated by its accuracy;loss curve;recall;F1 score;confusion matrix;receiver operating characteristic(ROC)curve;and precision-recall(PR)curve in the tasks of predicting stained tongue coating images in the testing dataset.The accuracy of the deep learning model was compared with that of attending physicians of traditional Chinese medicine(TCM).Results The training results showed that after 90 epochs;the model presented an excellent classification performance.The loss curve and accuracy were stable;showing no signs of overfitting.The model achieved an accuracy;recall;and F1 score of 92%;91%;and 92%;re-spectively.The confusion matrix revealed an accuracy of 92%for the model and 69%for TCM practitioners.The areas under the ROC and PR curves were 0.97 and 0.95;respectively.Conclusion The deep learning model constructed using ResNet50 can effectively recognize stained coating images with greater accuracy than visual inspection of TCM practitioners.This model has the potential to assist doctors in identifying false tongue coating and prevent-ing misdiagnosis.

Lactiplantibacillus plantarum AR113 alleviates microbiota dysbiosis of tongue coating and cerebral ischemia/reperfusion injury in rat

Stroke is one of the leading causes of death and disability worldwide.However,information on stroke-related tongue coating microbiome(TCM)is limited,and whether TCM modulation could benefit for stroke prevention and rehabilitation is unknown.Here,TCM from stroke patients(SP)was characterized using molecular techniques.The occurrence of stroke resulted in TCM dysbiosis with significantly reduced species richness and diversity.The abundance of Prevotella,Leptotrichia,Actinomyces,Alloprevotella,Haemophilus,and TM7_[G-1]were greatly reduced,but common infection Streptococcus and Pseudomonas were remarkably increased.Furthermore,an antioxidative probiotic Lactiplantibacillus plantarum AR113 was used for TCM intervention in stroke rats with cerebral ischemia/reperfusion(I/R).AR113 partly restored I/R induced change of TCM and gut microbiota with significantly improved neurological deficit,relieved histopathologic change,increased activities of antioxidant enzymes,and decreased contents of oxidative stress biomarkers.Moreover,the gene expression of antioxidant-related proteins and apoptosis-related factors heme oxygenase-1(HO-1),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),nuclear factor erythroid 2-related factor 2(Nrf2),NAD(P)H:quinone oxidoreductase-1(NQO-1),and Bcl-2 was significantly increased,but cytochrome C,cleaved caspase-3,and Bax were markedly decreased in the brain by AR113 treatment.The results suggested that AR113 could ameliorate cerebral I/R injury through antioxidation and anti-apoptosis pathways,and AR113 intervention of TCM may have the application potential for stroke prevention and control.

ISO/TR 20498-5 Traditional Chinese Medicine-Computerized tongue image analysis system-Part 5:Method of acquisition and expression of tongue colour and tongue coating colour

International Organization for Standardization(ISO)officially released ISO/TR 20498-5 Traditional Chinese medicine-Computerized tongue image analysis system--Part 5:Method of acquisition and expression of tongue colour and tongue coating colour on January 11,2019.ISO/TR 20498-5 was formulated by the team of Professor Wang Yiqin,from School of Basic Medicine of Shanghai University of TCM and Shanghai Key Laboratory of Health Identification and Evaluation,and jointly completed by East China University of Science and Technology and Suzhou Jingyu Medical Instrument Co.,LTD.

Study on Tongue Coating Microbiota in Patients with Atrophic Gastritis

Aims: To explore the tongue coating microbiota composition in patients with atrophic gastritis by using the 16S rRNA gene sequencing technology. Methods: The study included 29 atrophic gastritis patients and 29 age and gender-matched non-atrophic gastritis controls. By sequencing the V3-V4 region of the 16S rRNA, we investigated the microbial community structure and diversity on the tongue coating. Results: There was no significant difference in the microbial diversity on the tongue coating between the two groups. However, compared with the control, the atrophic gastritis group had a smaller number of operational taxonomic units (OTUs). At the class level, patients with atrophic gastritis had lower relative abundances of Betaproteobacteria and Spirochaetia than the control group. At the gene level, the abundance of Neisseria and Aggregatibacter in atrophic gastritis group had significantly decreased compared with control ones. Furthermore, functional prediction revealed that 24 metabolic pathways significantly differed between the two groups. Conclusions: Our findings provide novel evidence that tongue coating microbiota may be a biomarker for characterizing patient with atrophic gastritis, but its mechanism needs to be further elaborated.

Behavior of NiCrAlY coating on the TC6 titanium alloy

A NiCrAlY coating was deposited on the TC6 titanium substrate by arc ion plating （ALP）. The structure and morphologies of the NiCrAlY coating were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, and the influence of vacuum heat treatment on the element diffusion behavior was studied. The results showed that the y＇-Ni3Al phase was precipitated on the NiCrAlY coating after heat treatment. The Ni3（AI,Ti）, TiNi, and Ti2Ni intermetallic layers appeared at the interface from the outside to the inside at 700℃, and the thickness of the intermetallic layers increased with the increase in temperature. At 700℃ Ti and Ni were the major diffusion elements, and the diffusion of Cr was observed when the heat treatment temperature increased up to 870℃. The violent inward diffusion of Ni at 950℃ resulted in the degradation of the NiCrAlY coating.

Application value of tongue coating microflora in integration of traditional Chinese medicine and modern medicine

Observation of tongue coating is the characteristic content of traditional Chinese medicine syndrome differentiation and treatment. The microflora is the important component of tongue coating besides the desquamated epithelial cells. Tongue coating microflora might be an important linkage between the modern medical research and the classic traditional Chinese medicine theory. Therefore, the present paper summarised the application value of tongue coating microflora in health and disease to enrich the scienti fic connotation of traditional Chinese medicine tongue diagnosis and promote the development of integration of traditional Chinese medicine and modern medicine.

Thick tongue coating: diagnostic markers for metastatic colorectal cancer?

Background:According to World Health Organization,colorectal cancer is the third most common cancer in the world.The prognosis assessment and condition judgment of the colorectal cancer remains a challenge clinically.Therefore,identification of diagnostic markers to evaluate the prognosis of colorectal cancer clinically should be urgently developed.We have observed that a lot of cancer patients had thick tongue clinically,but what is the relationship between tongue coating and the tumor?Methods:Seventy-four patients with colorectal carcinoma were collected through the outpatients of Tianjin Medical University Cancer Institute and Hospital from May 2010 to September 2011,in which there were 49 patients confirmed with recurrence or metastasis.All photos of patients’tongue were taken with a SONY camera in the same room and under constant conditions such as brightness or distance.Regression equation predicting thickness of tongue coating was constructed using binary logistic regression analysis.The optimal cut off of probabilities to diagnosis thick tongue coating was determined by receiver operating curve analysis.χ2 test for paired data and kappa test were used to determine the diagnostic value for recurrence and/or metastasis in colorectal cancer patients.Kolmogorov-Smirnov test was used to determine the distribution of ALT,AST,ALP ALB,TP,GLO,TBIL,DBIL,GGT,LDH,GLU,UA,CA724,CA199,CA242 and CEA.Data with the skewed distribution were presented as median(quartile interval).The association between the thickness of tongue coating and clinical-pathological character was evaluated by chi square test and two-independent-sample test.The two-independent-samplesχ2 was used to determine whether there were significant differences in the thin coating and thick coating between patients with recurrence and/or metastasis and patients without recurrence and/or metastasis.Kaplan-Meier method was used to analyze survival time.Statistical analysis was performed by SPSS(version 16.0).Results:Through retrospective clinical study we found that overall survival of colorectal cancer patients with thick greasy tongue coating is less than the patients with less tongue coating.What’s more,the risk for recurrence or/and metastasis overall survival in thick coating group was higher than thin coating group.In addition,the histological staining of the tongue slices of rats showed that EGFR receptors in the tongue root were the most among whole tongue surface.Tongue thick coating may be due to tumor patients with high levels of serum EGF which results in significantly increasing tongue coating.This finding suggested that the tongue coating of cancer patients may reflect the level of serum EGF levels in patients which may be related to shorter survival time.In addition,another study showed that serum lactic dehydrogenase level in patients with thick tongue coating is higher than patients with thin tongue coating.Conclusions:These studies suggest that tongue coating is likely to reflect some of the growth factor and enzyme levels.By observing the tongue coating we could predict the prognosis of patients and the characteristics of tongue coating may be used as new diagnostic markers to patients with colorectal carcinoma.

NFAT3在充血性心力衰竭气虚血瘀证患者舌苔液中的表达及意义

目的研究活化T细胞核因子3(nuclear factor of activated T-cells 3,NFAT3)在充血性心力衰竭(congestive heart failure,CHF)气虚血瘀证患者舌苔液中的表达及与临床指标相关性,初步拟定该证候的诊断界值。方法收集CHF气虚血瘀证患者及健康对照者各30例,酶联免疫吸附法(enzyme linked immunosorbent assay,ELISA)检测舌苔液中NFAT3的含量。结果NFAT3在CHF气虚血瘀证患者舌苔液的含量为(481.40±103.00)pg/mL,明显高于健康对照者舌苔液的含量[(237.90±156.50)pg/mL](P<0.01);且随着美国纽约心脏协会(New York Heart Association,NYHA)心功能分级的增加,CHF气虚血瘀证患者舌苔液中NFAT3含量不断升高(P<0.01);CHF气虚血瘀证患者舌苔液NFAT3与NYHA心功能分级呈正相关性(r=0.927,P<0.01),与B型脑钠肽(brain natriuretic peptide,BNP)(r=0.806,P<0.01)呈正相关性,与左室射血分数(left ventricular ejection fraction,LVEF)呈负相关性(r=-0.739,P<0.01)。绘制受试者操作特性曲线(receive operating characteristic,ROC)初步拟定舌苔液清中NFAT3诊断CHF气滞血瘀证的界值为363.37 pg/mL,曲线下面积为0.91。结论NFAT3能够反映CHF病情轻重程度,可为CHF气虚血瘀证提供客观化、量化的参考和依据。

舌诊在慢性肝病中的应用刍议

舌诊作为中医特色诊法之一,在肝病的诊治与预防中具有重要意义。慢性肝病患者在不同的病理阶段有不同的舌象改变。舌色可反映肝病轻重缓急,如缓解期多见淡红舌,发作期多见红绛舌,而严重肝病多见青紫舌;舌形可反映肝病形气神,其中长条舌、圆柱舌是慢性肝病的常见舌形,舌缘肿大或者肝积舌多代表慢性肝病中的占位性病变;舌苔与肝病轻重及疾病预后有关,还可辅助诊断慢性肝病的细菌感染情况。此外,舌象在慢性肝病的临床用药指导中也具有重要意义,可多方面、多角度指导临床。

舌苔形成的调控机制及研究新思路

舌苔是舌背黏膜表面的一层苔状物,观察其颜色和性质变化是中医舌诊的重要内容。越来越多的证据显示,舌苔图像及其成分对系统性疾病具有重要的诊断价值,为中医察舌苔辅助临床辨证论治、遣方用药的科学内涵提供了现代科学证据。然而,关于舌苔形成的细胞与分子生物学机制依然缺乏系统深入研究。笔者分析了免疫-神经-内分泌系统、生物毒素、物理因素对舌苔形成的调控作用,为探索舌苔微环境(微生物、免疫、内分泌、机械拉伸、温度等)调控舌苔形成的生物学机制提供了新的研究思路和技术体系,有助于推动舌诊原理的现代科学内涵和临床应用研究。

奥密克戎变异株新型冠状病毒感染患者舌象特征与核酸循环阈值等实验室指标的关系

目的:探讨奥密克戎变异株新型冠状病毒感染(Corona Virus Disease 2019,COVID-19)普通型患者舌象特征与实验室指标的关系。方法:收集2022年4月-5月在上海城市足迹亚定点医院住院的165例临床确诊COVID-19普通型患者的舌象资料和实验室指标。舌象主要包括舌色、舌形、苔色、苔质。舌色分为淡红舌、淡白舌、红舌(包括绛舌)、青紫舌;舌形根据舌体形态分为正常舌、胖大舌(包括齿痕舌)、瘦薄舌;苔质根据舌苔厚薄程度分为薄苔、薄腻苔、厚腻苔,根据舌苔润燥程度分为润苔、燥苔;苔色分为白苔、黄苔。实验室指标包括核酸开放读码框基因(Open Reading Frame,ORF)和核壳蛋白基因(Nucleocapsid,N)的新冠病毒核酸循环阈(Cycle threshold,Ct)值、白细胞计数(White Blood Cell Count,WBC)、中性粒细胞/淋巴细胞值(Neutrophil/Lymphocyte Ratio,NLR)、C反应蛋白(C-reactive Protein,CRP)、降钙素原(Procalcitonin,PCT)、D-二聚体(D-dimer,DD)、丙氨酸氨基转移酶(Alanine Aminotransferase,ALT)、门冬氨酸氨基转移酶(Aspartate Ami-notransferase,AST)、白蛋白(Albumin,ALB)、乳酸脱氢酶(Lactate Dehydrogenase,LDH)、肌酐(Creatinine,Cr),并记录核酸阳性持续天数,分析不同舌象与上述指标的关系。结果:纳入的165例COVID-19普通型患者中淡红舌72例、淡白舌21例、红舌46例、青紫舌26例;正常舌69例、胖大舌64例、瘦薄舌32例;薄苔47例、薄腻苔33例、厚腻苔85例;润苔83例、燥苔82例;白苔88例、黄苔77例。淡白舌、红舌、青紫舌、胖大舌、瘦薄舌、燥苔患者核酸Ct值分别较淡红舌、正常舌、润苔患者降低(P<0.05);淡白舌、青紫舌、瘦薄舌、燥苔患者的核酸阳性持续时间与淡红舌、正常舌、润苔患者相比,分布有差异(P<0.05);胖大舌、瘦薄舌患者的CRP值高于正常舌患者(P<0.05);厚腻苔患者的PCT高于薄苔患者(P<0.05);厚腻苔、黄苔患者的NLR分别高于薄腻苔、薄苔、白苔患者(P<0.05);胖大舌、黄苔患者的ALB值低于及瘦薄舌、正常舌、白苔患者(P<0.05);厚腻苔患者的Cr值高于薄腻苔患者(P<0.05)。结论:不同舌象特征COVID-19普通型患者实验室指标存在差异,舌色、舌形、舌苔润燥程度与核酸Ct值、核酸阳性持续时间关系密切,淡白舌、青紫舌、胖大舌、瘦薄舌及燥苔患者的病毒载量较高,核酸转阴延迟;而不同苔质、苔色、舌形患者炎症指标存在差异,厚腻苔患者的肾功能损害更为严重。

结直肠癌患者舌苔变化与舌苔菌群和肠道菌群的相关性研究

目的:探讨结直肠癌患者腻苔舌苔变化与舌苔菌群和肠道菌群的相关性。方法:选取2022年9月至2023年3月哈尔滨医科大学附属第一医院结直肠外科收治的63例结直肠癌患者,根据其舌象特征分层随机抽样采集其中12例黄腻苔和9例白腻苔患者的舌苔、癌组织及癌旁组织样本,同时采集6例肠镜检查无异常的薄白苔健康人舌苔样本。所有样本均行高通量5R 16S rDNA测序分析。结果:结直肠癌患者舌苔变化以黄腻苔和白腻苔为主。舌苔奇异菌属(Atopobium)和肠道颗粒链菌属(Granulicatella)可能是黄腻苔结直肠癌患者的特征性菌属;舌苔孪生球菌属(Gemella)和肠道罗氏菌属(Roseburia)、希瓦氏菌属(Shewanella)可能是白腻苔结直肠癌患者的特征性菌属。具核梭杆菌(Fusobacterium nucleatum)、龋齿放线菌(Actinomyces odontolyticus)和口炎消化链球菌(Peptostreptococcus stomatis)或分别为黄腻苔和白腻苔结直肠癌患者潜在的口-肠相关菌。结论:结直肠癌患者舌苔变化与舌苔、肠道菌群结构和丰度的变化相关,舌苔菌群与癌组织菌群、癌旁组织菌群不同的重叠种类及程度提示中医舌诊腻苔的变化能反映出结直肠癌口-肠菌群的特征性变化,为后期研究中药靶向微生物干预结直肠癌的发展提供客观依据。

TC11钛合金表面电弧离子镀TiAlN涂层防护性能的研究

利用电弧离子镀技术在TC11钛合金基体上沉积TiA lN涂层。采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)等方法对比分析了钛合金基体和涂层氧化前后的表面形貌、物相结构。采用X射线光电子能谱仪(XPS)对TiA lN涂层性能进行了分析,研究了基体和镀膜的耐磨性。结果表明,TiA lN涂层显著改善了钛合金的粘着磨损性及高温抗氧化性,在空气中650℃静态氧化100 h后,TiA lN涂层依然保持良好的状态和抗磨损性能。

面向早期筛查的血糖失稳态人群“舌象-舌苔微生物组学”特征与机制研究

血糖失稳态是糖尿病、冠心病、脑卒中、痴呆、恶性肿瘤等许多慢性重大性疾病的独立风险因素,临床危害极大,但其高度可逆性的特点也给上述重大疾病的早期防治提供了机会窗口。然而,当前针对血糖失稳态人群早期筛查及干预尚无系统性研究,对其中重要组成部分的糖尿病前期人群所用筛查方法在特异性、准确性方面均存在不足,临床应用受限。在中医临床实践中,舌象是反映正邪消长和病情进退的重要依据,特别是在“血糖稳态—血糖失稳态—糖尿病”病程进展中舌象具有一定的动态演化特点,而其舌象变化的潜在机制可能与舌苔微生物密切相关。基于血糖失稳态人群“舌象-舌苔微生态”的临床表观与微生物组学特征构建“舌象-舌苔微生物”宏微观映射模型,有望为血糖失稳态人群的大规模早期筛查和相关疾病早期防治提供新路径,并为阐明中医舌象诊断理论科学内涵、探讨复杂性疾病演化特点与潜在机制提供新视角。

TC-RT-PCR技术在马铃薯病毒检测及其基因克隆上的应用

利用试管捕捉RT-PCR(TC-RT-PCR)技术从马铃薯病毒发病叶片中检测并克隆到PVX、PVY和PLRV3种病毒及其外壳蛋白基因的全长序列,长度分别为714、804和627 bp。结果表明,TC-RT-PCR技术是一种简单,快捷,灵敏度高的方法,在马铃薯病毒的检测和相关基因的克隆中将会得到很好的应用。

2型糖尿病勃起功能障碍患者舌象特点及舌苔微生物群落关联性分析

目的探索2型糖尿病勃起功能障碍(Type 2 diabetes mellitus Erectile dysfunction,T2DMED)患者舌象特点及其舌苔微生物群落结构相关性。方法选取2022年4月18日—2023年6月28日期间就诊于中国中医科学院西苑医院男科门诊的45例T2DMED作为病例组,34例2型糖尿病(Type 2 diabetes mellitus,T2DM)作为对照组,采集舌图、舌苔菌群和血糖及性激素水平。采用16S rRNA基因高通量测序技术检测舌苔菌群,对其进行Alpha多样性、β多样性、组间差异性分析,并利用KEGG数据库进行功能预测。结果发现T2DMED患者暗红舌、黄苔、厚苔、腻苔、胖大舌、裂纹舌、瘀点舌、瘀斑舌出现率均明显高于T2DM组,差异有统计学意义(P<0.05)。T2DMED与T2DM舌苔微生物的物种多样性及物种构成整体上,差异无统计学意义(P>0.05)。但在门和属两个水平上,差异有统计学意义(P<0.05),在门水平上有2个差异物种,分别是变形菌门和蓝细菌;在属水平上有18个差异物种,主要为奈瑟菌属、普雷沃氏菌属等。在舌苔方面隐藏真杆菌属与腻苔呈显著的负相关性,差异有统计学意义(P<0.05);颤螺旋菌属、毛螺菌科NC2004和颤杆菌属与厚苔呈显著的正相关性,差异有统计学意义(P<0.05)。此外,两组患者在脂质代谢、辅因子和维生素代谢等通路上,差异有统计学意义(P<0.05)。结论暗红舌、黄苔、厚苔、腻苔、胖大舌、裂纹舌、瘀点舌、瘀斑舌是T2DMED的特征性舌象。T2DMED与T2DM苔微生物的物种多样性及物种构成整体上不具有显著性的差异,某些特定舌苔菌群可作为T2DMED的生物标志物,T2DMED患者腻苔、厚苔和糖化血红蛋白(Hemoglobin A1C,HbA1c)与部分舌苔菌群有关。

^(99)Tc^m-5-氨基水杨酸包衣片在结肠的定位释药

采用放射性核素示踪技术研究了5-氨基水杨酸包衣片对犬结肠的靶向性。用99Tcm标记5-氨基水杨酸后,将标记物制成包衣片;通过在人工胃、肠液中测定放射性泄漏的方法观察包衣片的包衣膜性能;实验犬口服包衣片后,用SPECT显像观察包衣片在犬消化道内的运动过程。结果显示:包衣片在人工胃液中不溶解,外观无变化,无放射性漏出;将包衣片在人工胃液中滞留1h,取出放入人工肠液中3h,包衣膜被部分溶蚀,出现大量孔洞,但无放射性漏出;3.5h后有放射性漏出,表明包衣膜开始破裂释药。犬口服后,包衣片在升结肠开始释药,并在结肠内停留6～7h。表明5-氨基水杨酸包衣片能在结肠定位释药。

基于持续学习的中医舌色苔色协同分类方法

中医(traditional Chinese medicine, TCM)舌诊客观化研究中需要分析的舌象特征很多,不同的舌象特征往往采用单独的方法进行分析,导致分析系统的整体实现复杂度大幅增加。为此,基于持续学习的思想,提出一种中医舌色苔色协同分类方法,该方法将舌色分类作为旧任务,将苔色分类作为新任务,充分利用2个任务的相似性和相关性,仅通过一个网络结构就同时实现舌色和苔色的准确分类。首先,设计一种基于全局-局部混合注意力机制(global local hybrid attention, GLHA)的双分支网络结构,将网络高层语义特征与低层特征相融合,提升特征的表达能力;然后,提出基于正则化和回放相结合的持续学习策略,使得该网络在学习新任务知识的同时有效防止对旧任务知识的遗忘。在2个自建的中医舌象特征分析数据集上的实验结果表明,提出的协同分类方法可以获得与单个任务相当的分类性能,同时可以将2个分类任务的整体复杂度降低一半左右。其中,舌色分类准确率分别达到93.92%和92.97%,精确率分别达到93.69%和92.87%,召回率分别达到93.96%和93.16%;苔色分类准确率分别达到90.17%和90.26%,精确率分别达到90.05%和90.17%,召回率分别达到90.24%和90.29%。

大肠进展期腺瘤舌苔菌群微生态分析

目的探究大肠进展期腺瘤患者舌苔菌群微生态的特点。方法纳入2023年2月至2023年4月就诊于北京中医药大学东方医院消化内镜中心的大肠进展期腺瘤患者共15例,体检中心健康人共30名,使用口腔咽拭子刮取舌苔,进行16S rRNA扩增并进行高通量测序,对测序结果进行微生态分析。结果大肠进展期腺瘤组与健康人群组在菌群的Alpha多样性方面差异无统计学意义(P>0.05);Beta多样性方面差异有统计学意义(P<0.05)。大肠进展期腺瘤组中放线菌门(Actinobacteria)、奇异菌属(Atopobium)、放线菌属(Actinomyces)、罗氏菌属(Rothia)的相对丰度显著高于健康人群组(P<0.05)。大肠进展期腺瘤组中巨球形菌属(Megasphaera)、Oribacterium、韦荣氏球菌属(Veillonella)相对丰度显著低于健康人群组(P<0.05)。结论大肠进展期腺瘤患者的舌苔菌群与健康人群相比存在差异,其中主要表现在奇异菌属(Atopobium)、放线菌属(Actinomyces)、罗氏菌属(Rothia)的增加,巨球形菌属(Megasphaera)、Oribacterium、韦荣氏球菌属(Veillonella)丰度的减少。

TC11表面激光熔覆MCrAlY涂层温度场模拟及参数优化

采用ADPL参数化语言,综合考虑热源模型、材料热物性参数、相变潜热、边界条件等因素,建立了连续移动高斯热源作用下TC11表面激光熔覆MCrAlY涂层三维瞬态温度场数值模型。实验结果测量值与模拟计算值的对比表明,建立的温度场数值模型具有很好的可靠性。同时,在分析涂层品质的基础上,基于该模型对TC11表面激光熔覆MCrAlY涂层的激光工艺参数进行了预报及优化,得出较优的激光工艺参数为:激光功率1 200 W、光斑直径2 mm、扫描速度400mm/min。