Analysis of effective stresses for titanium alloys in continuous forming process

2021 ◽  
Author(s):  
Mulualem Hailu Besha ◽  
Devendra Kumar Sinha ◽  
C. Venkatesh ◽  
Satyam Shivam Gautam
Keyword(s):  
Titanium Alloys ◽  
Forming Process ◽  
Continuous Forming ◽  
Effective Stresses

scholarly journals Forming of Hollow Shaft Forging From Titanium Alloy Ti6Al4V by Means of Rotary Compression

2015 ◽  
Vol 60 (1) ◽  
pp. 419-425 ◽  
Author(s):  
J. Tomczak ◽  
Z. Pater ◽  
T. Bulzak
Keyword(s):  
Titanium Alloys ◽  
Automotive Industry ◽  
Experimental Tests ◽  
Aviation Industry ◽  
Forming Process ◽  
Compression Process ◽  
Hollow Shaft ◽  
Experimental Works ◽  
Titanium Alloy Ti6al4v ◽  
Hollow Shafts

Abstract This paper presents chosen results of theoretical-experimental works concerning forming of hollow shafts forgings from titanium alloys, which are applied in aviation industry. At the first stage of conducted analysis, the forging forming process was modeled by means of finite element method. Calculations were made using software Simufact Forming. On the basis of performed simulations optimal parameters of rotary compression process were determined. Next, experimental tests of forging forming in laboratory conditions were made. For the research needs, a forging aggregate, designed by the Authors, was used. Conducted research works confirmed the possibility of metal forming (by means of rotary compression) of hollow shafts from hard workable titanium alloys. Numerous advantages of rotary compression process, make it attractive both for low series production (aircraft industry) and for mass production (automotive industry).

scholarly journals Microstructural and mechanical studies of feedstock material in continuous extrusion process

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Tariku Desta ◽  
Devendra Kumar Sinha ◽  
Perumalla Janaki Ramulu ◽  
Habtamu Beri Tufa
Keyword(s):  
Yield Strength ◽  
Statistical Significance ◽  
Extrusion Process ◽  
Wheel Speed ◽  
Forming Process ◽  
Percentage Elongation ◽  
Continuous Forming ◽  
Before And After ◽  
Continuous Extrusion ◽  
Feedstock Material

AbstractThe challenge encountered in continuous forming process is the variation in mechanical strength of product formed with respect to process variables like extrusion wheel speed and diameter of product. In this research article, the micro-structural investigation of the aluminum (AA1100) feedstock material of 9.5-mm diameter has been carried out at various extrusion wheel speeds and diameter of product before and after deformation on commercial continuous extrusion setup TBJ350. The mechanical properties like yield strength as well as percentage elongation have been estimated and optimized using two variables with 3 levels through central composite rotatable design (CCRD) method. The mathematical modeling has been carried out to predict the optimum combination of process parameters for obtaining maximum value of yield strength and percentage elongation. The statistical significance of mathematical model is verified through analysis of variance (ANOVA). The optimum value of yield strength is found to be 70.939 MPa at wheel velocity of 8.63 rpm and product diameter of 9 mm respectively, whereas the maximum percentage elongation recorded is 46.457 at wheel velocity of 7.06 rpm and product diameter of 7.18 mm. The outcome may be useful in obtaining the best parametric combination of wheel speed and extrusion ratio for best strength of the product.

scholarly journals Process Development for a Superplastic Hot Tube Gas Forming Process of Titanium (Ti-3Al-2.5V) Hollow Profiles

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1150
Author(s):  
Ricardo Trân ◽  
Franz Reuther ◽  
Sven Winter ◽  
Verena Psyk
Keyword(s):  
Titanium Alloys ◽  
Process Development ◽  
Chemical Properties ◽  
Superplastic Forming ◽  
Process Window ◽  
Forming Process ◽  
Time Curve ◽  
Pressure Time ◽  
Tool Technology ◽  
Good Agreement

Tube forming technologies based on internal forming pressures, such as hydroforming or hot tube gas forming, are state of the art to manufacture complex closed profile geometries. However, materials with excellent specific strengths and chemical properties, such as titanium alloys, are often challenging to shape due to their limited formability. In this study, the titanium alloy Ti-3Al-2.5V was processed by superplastic hot tube gas forming to manufacture a helically shaped flex tube. The forming process was investigated in terms of process simulation, forming tool technology and process window for the manufacturing of good parts. Within a simulation study, a strain rate optimized forming pressure–time curve was defined. With the newly developed tool design, forming temperatures up to 900 °C and internal forming pressures up to 7 MPa were tested. A process window to manufacture good parts without necking or wrinkling has been successfully identified. The experiment data showed good agreement with the numerical simulations. The detailed study of the process contributes to an in-depth understanding of the superplastic forming of Ti-3Al-2.5V during hot tube gas forming. Furthermore, the study shows the high potential of superplastic hot tube gas forming of titanium alloys for the manufacturing of helical flex tubes and bellows.

Effect of Accurate Dimension Part during Transfer Die Technology

2015 ◽  
Vol 1096 ◽  
pp. 381-386
Author(s):  
Sanya Kumjing
Keyword(s):  
Finite Element ◽  
High Precision ◽  
P Value ◽  
Forming Process ◽  
Continuous Forming ◽  
Significance Level ◽  
Forming Simulation ◽  
Statistical Confidence ◽  
Element Simulation ◽  
Thick Steel

This research aimed to apply the transfer die technology together with the forming simulation by using finite element method to assist the analysis and the design of a high-precision continuous forming die for the panel auto part forming, which was made from 1.4 mm thick steel JFS A3001. The outcome of the finite element simulation of a specimen could be applied in forming a specimen without any specimen damage. Therefore, the high-precision continuous forming die was designed based on the results and factors from the forming simulation. After the design, the high-precision continuous forming die was manufactured and the specimen stamping test was conducted to satisfy the customer’s specifications. The results from the testing shown that the specimens obtained from the forming process are similar to the sample provided from the customer. Only minor forming die modification was required. In addition, the results of specimens inspection according to the inspection location using measuring tools shown that the size and the circumference of the specimens were in an acceptable range with more than 0.05 significance level of P-value (P-Value >α) and 95% statistical confidence level. As a result, die manufacturers can effectively save time, reduce cost and minimize risk occurred from errors in the die manufacturing.

scholarly journals Single-Point Incremental Forming of Titanium and Titanium Alloy Sheets

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6372
Author(s):  
Valentin Oleksik ◽  
Tomasz Trzepieciński ◽  
Marcin Szpunar ◽  
Łukasz Chodoła ◽  
Daniel Ficek ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Elevated Temperatures ◽  
Incremental Forming ◽  
Single Point ◽  
Production Costs ◽  
Electrical Heating ◽  
Single Point Incremental Forming ◽  
Forming Process ◽  
Shape Accuracy

Incremental sheet forming of titanium and its alloys has a significant role in modern manufacturing techniques because it allows for the production of high-quality products with complex shapes at low production costs. Stamping processes are a major contributor to plastic working techniques in industries such as automotive, aerospace and medicine. This article reviews the development of the single-point incremental forming (SPIF) technique in titanium and its alloys. Problems of a tribological and microstructural nature that make it difficult to obtain components with the desired geometric and shape accuracy are discussed. Great emphasis is placed on current trends in SPIF of difficult-to-form α-, α + β- and β-type titanium alloys. Potential uses of SPIF for forming products in various industries are also indicated, with a particular focus on medical applications. The conclusions of the review provide a structured guideline for scientists and practitioners working on incremental forming of titanium and titanium alloy sheets. One of the ways to increase the formability and minimize the springback of titanium alloys is to treat them at elevated temperatures. The main approaches developed for introducing temperature into a workpiece are friction heating, electrical heating and laser heating. The selection of an appropriate lubricant is a key aspect of the forming process of titanium and its alloys, which exhibit unfavorable tribological properties such as high adhesion and a tendency to adhesive wear. A review of the literature showed that there are insufficient investigations into the synergistic effect of rotational speed and tool rotation direction on the surface roughness of workpieces.

Rolling Process for the Continuous Forming of Curved Surface Parts Based on Bended Rolls

2013 ◽  
Vol 684 ◽  
pp. 334-337
Author(s):  
Zhong Yi Cai ◽  
Mi Wang ◽  
Ming Zhe Li
Keyword(s):  
Convex Surface ◽  
Three Dimensional ◽  
Rolling Process ◽  
Forming Process ◽  
Continuous Forming ◽  
Metal Forming Process ◽  
Longitudinal Bending ◽  
Roll Gap ◽  
Curved Surface Parts ◽  
Dimensional Surface

A new sheet metal forming process which can form three-dimensional surface rapidly, effectively and with lower-cost has been proposed. This paper mainly focuses on the fundamental aspects of the process. The principle of the rolling process based on bended rolls is introduced, and the methods to calculate the longitudinal bending deformation and to design the roll gap are presented. Experiments for typical surface parts are carried out. The forming results of convex surface and saddle shaped surface parts are measured and analyzed, the analyzed results demonstrated that the proposed process is a feasible and effective way of forming three-dimensional surface parts.

scholarly journals Accuracy and Sheet Thinning Improvement of Deep Titanium Alloy Part with Warm Incremental Sheet-Forming Process

2021 ◽  
Vol 5 (4) ◽  
pp. 122
Author(s):  
Badreddine Saidi ◽  
Laurence Giraud Moreau ◽  
Abel Cherouat ◽  
Rachid Nasri
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Thickness Distribution ◽  
Single Point ◽  
Sheet Forming ◽  
Incremental Sheet Forming ◽  
Fe Model ◽  
Forming Process ◽  
Shape Accuracy ◽  
Truncated Cone

Incremental forming is a recent forming process that allows a sheet to be locally deformed with a hemispherical tool in order to gradually shape it. Despite good lubrication between the sheet and the tip of the smooth hemisphere tool, ductility often occurs, limiting the formability of titanium alloys due to the geometrical inaccuracy of the parts and the inability to form parts with a large depth and wall angle. Several technical solutions are proposed in the literature to increase the working temperature, allowing improvement in the titanium alloys’ formability and reducing the sheet thinning, plastic instability, and failure localization. An experimental procedure and numerical simulation were performed in this study to improve the warm single-point incremental sheet forming of a deep truncated cone in Ti-6Al-4V titanium alloy based on the use of heating cartridges. The effect of the depth part (two experiments with a truncated cone having a depth of 40 and 60 mm) at hot temperature (440 °C) on the thickness distribution and sheet shape accuracy are performed. Results show that the formability is significantly improved with the heating to produce a deep part. Small errors are observed between experimental and theoretical profiles. Moreover, errors between experimental and numerical displacements are less than 6%, which shows that the Finite Element (FE) model gives accurate predictions for titanium alloy deep truncated cones.

Melting and Casting of Titanium Alloys

2007 ◽  
Vol 539-543 ◽  
pp. 3601-3606 ◽  
Author(s):  
Si Young Sung ◽  
Young Jig Kim
Keyword(s):  
Titanium Alloys ◽  
Fatigue Property ◽  
Unique Property ◽  
Specific Yield ◽  
Forming Process ◽  
Good Corrosion Resistance ◽  
The Past ◽  
Alpha Case ◽  
Near Net Shape ◽  
Net Shape Forming

Over the past decades, a large number of researchers have been trying titanium alloys in an attempt to combine most of their advantages, such as high specific yield strength, good corrosion resistance, excellent fatigue property and biocompatibility by casting route. However, the wide use of titanium alloys casting has been limited, since it is considered as only a near net shape forming process in titanium alloys due to the catastrophic reactivity of molten states, the alpha-case formations and the casting defects. In order to maximize the unique property of titanium alloys casting which are comparable to wrought products and quite often superior, it is necessary to take a close examination of titanium alloys casting procedure. Therefore, the merits and demerits of various melting devices, pouring methods and mold materials will be addressed with regard to improving titanium alloys casting.

Oxidation Behavior of Reheating Hot Work Die Steels

2012 ◽  
Vol 249-250 ◽  
pp. 896-899
Author(s):  
Ji Ung Choi ◽  
Ho Sung Lee
Keyword(s):  
Oxidation Behavior ◽  
Chemical Potential ◽  
Mass Gain ◽  
Reaction Rates ◽  
Forming Process ◽  
Continuous Forming ◽  
Temperature Oxidation ◽  
Die Steels ◽  
Hot Work Die ◽  
Forming Tools

At hot working condition, forming tools must be durable at operating temperatures during continuous forming process and especially dimensional stability and corrosion resistant property are required. In this paper, oxidation behavior of several hot work die steels was studied at elevated temperature forming condition. It is shown that test specimens begin to form oxides at the surface during the initial heating period. Transient oxidation is observed during the initial stage of oxidation, in which the initial fast reaction rates may be related to local thermal instabilities such as fast nucleation of oxide grains due to microstructural variation or chemical potential differences through the thin initial oxide layer. When initial mass gain does not contribute to steady state parabolic law, the Pieraggi model is successfully applied to the high temperature oxidation of tool steels. Based on this information, suitable forming die material was selected for reheating application above 850°C.

Elongation Rule of the Longitudinal Fiber of the Continuous Roll Forming Part

2018 ◽  
Vol 921 ◽  
pp. 184-188
Author(s):  
Yue Li ◽  
Shu Chen Yang ◽  
Mi Wang ◽  
Guo Long Lu
Keyword(s):  
Sheet Metal ◽  
Low Cost ◽  
Three Dimensional ◽  
Roll Forming ◽  
Longitudinal Deformation ◽  
Forming Process ◽  
Continuous Forming ◽  
High Efficient ◽  
Flexible Roll ◽  
Longitudinal Fiber

Continuous roll forming is a novel technique for low-cost, high-efficient manufacturing of three-dimensional surface part. Comparing with conventional continuous forming (using at least three rolls), continuous roll forming employs an upper and a lower flexible rolls to shape the sheet metal. The desired forming shape can be obtained by controlling the profile of the flexible roll and the gap between upper and lower flexible rolls. Modeling and simulation of the continuous roll forming process based on finite element analyses is established to investigate the elongation rule of the longitudinal fiber of the continuous roll forming part. The length of the longitudinal fiber at different positions across the thickness direction is discussed, and the mechanism of the longitudinal deformation is clarified. The following conclusions are obtained. When the flexible roll profile and the roll gap distribution meet certain conditions and make length of the longitudinal fiber linearly distributed, the longitudinal deformation of the sheet metal can be generated.

Sign in / Sign up

Export Citation Format

Share Document