Aluminum alloys are using widely duo to high strength-to-density ratio in the industries of automotive, shipbuilding and aerospace as a substitution of steel sheets. .To increases the formability of aluminum alloys in deep drawing process and due to formability problems of these alloys in room temperature using of warm deep drawing process is necessary. According to recent researches, warm deep drawing in gradient condition has better results as isothermal case. In this paper the process parameters in production of cylindrical parts from aluminum alloys 5083 sheet with 2mm thickness is investigated. For this purpose, gradient warm deep drawing in temperatures of ambient (25˚C), 80˚C, 150˚C, 180˚C, 250˚C, 350˚C , 450˚C and 550˚C have been used. The blank in flange region is heated by die heating and the blank center to increases the strength of the region which contact with punch corner radius is cooled by water circulating punch. The results show that increasing the temperature of the blank in flange region and also cooling of blank center lead to improve the limit drawing ratio. In forming temperature of 550˚C and ram speed of 378 mm/min and lubrication by graphite powder can reach to the limit drawing ratio equal to 2.83.  

Deep drawing of cylindrical shapes with high limiting drawing ratio (LDR) values is relatively difficult. Annealing is a further operation, which in turn adds costs and consumes significantly time to the forming process. In the present work, cylindrical cups from brass sheet were made with only limited anneal during few steps, but having LDR of 9 that is about 2 times higher than previous works. Cups having 4 mm IDs and 70 mm heights were made successfully. The process was simulated by ABAQUS/Explicit finite element (FE) code and experimental tests were carried out based on FEM results. Parameters affecting the process were studied with experimental results, as well as FEM. The wall thickness obtained from the approach were compared for several tests, and verified significantly.

Limit to the tension reinforcement ratio in flexural high strength reinforced concrete (HSRC) members is based on the requirement that tension failure as sufficient rotation capacity are ensured at ultimate limit state. However, the provisions for the maximum amount of compression reinforcement ratio (r'max) in a doubly reinforced section are not associated with any rational derivation. A quantitative measure to evaluate an upper limit to the compression reinforcement ratio (r'max) of such flexural HSRC members is proposed. The quantitative criterion to r'max can be derived from i) steel congestion and ii) considerations that are related to the diagonal compression bearing capacity of the members.In this paper it is shown that, when flexural loading is dominant the shear loading, the limit to ρ' is set by the steel congestion criterion. Parameters that affect this limit such as, f'c, beams geometry (cross sectional dimension and concrete cover), and bars diameter are deeply investigated and the expressions were derived to provide an additional tool for a better design and assessment of the flexural capacity of HSRC members considering different end conditions and loading arrangement.

Hydroforming process in one of the most effective production method, for improving the drawing ratio in sheet metal forming process. This is due to the fact that in hydroforming process, forming takes place using a punch which drives the part forward via a controlled fluid pressure. In this paper, deep drawing hydroforming for circular punch is investigated. Different pressure paths are tested using ABAQUS 6.7 software, in order to determine practical pressure constraint via simulation. Finally, drawing ratio effect on practical pressure constraint is investigated. In order to evaluate simulation accuracy, the obtained results are compared with some experimental results. Results indicate that by increasing drawing ratio, rupture curve is dropped significantly, and allowed zone area is reduced. Moreover, with increasing time, allowed zone area is expanded, and with increasing drawing ratio, allowed zone distance is reduced.

Cold drawing process is one of the most used metals forming processes in industries for formingseamless tubes. This process of plastic deformation of metals occurs below the recrystallization temperature and isgenerally performed at room temperature. When metal is cold worked, upon the release of forming force, thespringback occurs. In this paper, the springback effect of the seamless tube that has undergone cold drawing isstudied for three different reduction ratios viz. 10-15 %, 15-20 %, and 20-25 % having the aim to reduce it. Experiments are conducted under different reduction ratios with working conditions of die semi angles of 10 and15 degrees, die land width of 5 mm and 10 mm as well as drawing speed of 4, 6, and 8 m/min for C-45 tubematerial. Optimum reduction ratio is finalized using Statistical Package for Social Science (SPSS) software of dataanalysis using statistical tests like Kruskal-Wallis, ANOVA, Post-hoc, etc. Metallurgical analysis throughmicrostructural investigation, XRD and mechanical testing via cold draw load, and hardness testing for differentreduction ratios are also studied for validation purposes. The results of this research show that 10-15 % reductionratio yields the minimum springback. This can be used to help designing tools in the metal forming industry tominimize springback and improve the quality of the product.

Up to now a large number of models have been developed to measure or predict the damage in equipments. Some of these models have been implemented in ABAQUS software. To implement damage parameters in the software, it is necessary to perform complex and expensive practical tests. One of these damage models is Forming Limit Diagram (FLD).The purpose of this research is deriving required parameters for modeling damage by numerical method and using of software. To study and compare of the accuracy of this method, these parameters have been derived with experimental method. FLD parameters for metastable austenitic stainless steel 304 have been extracted from Erichsen test and then phase change from austenite to martensite during deep drawing have been modeled with CLEMEX and SIGMAPLOT software. By defining changes of physical and mechanical properties of elastic-plastic material, the obtained results are transmitted to ABAQUS via developing a VUMAT subroutine in FORTRAN. Then Erichsen test has been simulated in ABAQUS and aforementioned subroutine was used to define changes of properties in simulation. Critical points susceptible for necking in all test cups are determined and numerical FLD was drawn based on principal strains in these points. Finally, the results of this method and practical tests were compared.

Introduction: This study was conducted to investigate the predictive value of NLR and PLR with staging and grading of bladder tumors in Iran for the first time; as well as producing comprehensive data to attain defined cut-offs.Methods: The medical records of 454 patients between 2016 and 2022 have been collected and diagnosed with bladder cancer by cystoscopy and transurethral resection of bladder tumor (TURBT). Clinical and demographic parameters including age, weight, diabetes, smoking, opium usage, and hematuria were registered. The stage of BC was defined based on the results of physical exams, biopsies, and imaging tests.Results: The study comprised 393 males and 61 females ranging from 28 to 97 years old. The cut-off of NLR as a predictor of grade was 3.09 and 3.78 for the stage, which was 100.8 and 109.6 for PLR respectively. Taller people had lower PLR. There was a relationship between PLR and smoking with non-smokers having significantly higher levels of PLR (P-values=0.039 and 0.025 for grade and stage respectively). Overall NLR (AUC=71.4 and 72.4% for grade and stage respectively) and PLR (70.6 and 73.8% for grade and stage respectively) have shown predictive value for stage and grade of BC in patients younger than 65.Conclusion: Our findings suggest that PLR and NLR can be reliable predictors of the stage and grade of BC in patients under 65 years old, however, their predictor values increase when data are stratified. Higher NLR was associated with opium usage and non-O blood type.

Nowadays, using aluminum alloys in construction of transportation vehicles to lighten final product weight and reduce fuel consumption has increased. To increases the formability of aluminum alloys and due to formability problems of these alloys in room temperature using of warm forming process is necessary. One of the forming processes at elevated temperatures is warm hydrodynamic deep drawing assisted by radial pressure. In the paper, after investigating the effect of Geometric Parameters and temperature (isothermal and non-isothermal) on thickness distribution and punch force, the effect of different parameters (temperature, media pressure and forming speed) on the limit drawing ratio was investigated. The result show that in the non-isothermal conditions, with increase in temperature, the maximum thickness reduction remained unchanged but the punch force was decreased. Additionally, the limit drawing ratio was increased with increasing temperature in the non-isothermal conditions, media pressure and forming speed and with decreasing temperature in the isothermal conditions. In this study maximum LDR is 2. 52, in non-isothermal warming condition and temperature of 250c.