Effect of the chassis parts surface condition from high-strength titanium alloy VT-22 in the process of fatigue tests

2021 ◽  
Vol 2021 (2) ◽  
pp. 45-53
Author(s):  
A. O. Gorpenko ◽  
◽  
O.I. Semenets ◽  
O. M. Doniy ◽  
K.O. Valuiska ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Surface Defects ◽  
Surface Condition ◽  
High Strength ◽  
Surface Damage ◽  
Cylindrical Part ◽  
Fatigue Tests ◽  
Landing Gear ◽  
Premature Failure ◽  
Surface Machining

The research focuses on the influence of the surface condition on the resource of high-strength titanium alloy VT-22 landing gear details during fatigue tests. The tests were performed on special facilities that simulate the workload on a rod detail at the stage of extending and retraction of the landing gear. Fatigue tests were performed on four rods. Rods № 1-3 were destroyed at the lugs level, rod №4 withstood the entire cycle of loads, and was examined in an undamaged state. It was found that the cause of the failure of the rod №1 was axial play formation as a result of bracket lug deformation, which led to shock loads on the lug of the rod №1 during the tests. The destruction of the rod №2 could be caused by the shock axial loads due to changes in the characteristics and load values of the facility on the rod №2. The priority factor influencing the premature failure of the rod №3 was the high risks from surface machining in the most loaded part of the rod №3, namely at the R-junction of the cylindrical part to the lug. The presence of surface defects formed during the manufacturing stage, as well as the presence of deep scratches in the area with high load reduce the life of rod № 3 fivefold compared to the undamaged rod № 4, which had no visible surface defects. Surface damage detected in the non-chromized area of the rods can be eliminated by blasting with subsequent surface polishing, which will provide the required resource of the detail (rod № 4). Keywords: high-strength titanium alloy VT-22, rod, fatigue tests, surface defects, structure of the surface layer.

scholarly journals USING THE LINEAR DAMAGE SUMMATION HYPOTHESIS IN THE FATIGUE TESTS ANALYSIS OF TITANIUM ALLOY PIECES

2021 ◽  
pp. 1-6
Author(s):  
Evgeniya Gnatyuk ◽  
Arkadiy Skvortsov ◽  
Svetlana Kuleshova
Keyword(s):  
Titanium Alloy ◽  
Endurance Limit ◽  
Linear Regression Analysis ◽  
High Strength ◽  
Fatigue Tests ◽  
Test Pieces ◽  
Operational Testing ◽  
Strength Material ◽  
Number Of Cycles ◽  
Damage Summation

This paper presents the results of fatigue tests of titanium alloy, and also describes the use of the hypothesis of linear damage summation when processing the results of fatigue tests. On the basis of the experiments, the endurance limit of the titanium alloy was determined, which lies in the range from 460 to 480 MPa with the number of cycles from 105 to 108. The purpose of the experiment was to determine the endurance limit of high strength material, as well as a mathematical measurement of the expected destruction. In this study, empirical methods were used such as indirect observation of the object under study, description and measurement of technical influences exerted on it by an artificial means, as well as linear regression analysis to establish the relationship between stress and durability. As a result of the experiment, fatigue curves were obtained for various probabilities, which give grounds to conclude that the use of the linear damage summation hypothesis in processing the results of fatigue tests entails a satisfactory practical accuracy of the calculation of endurance limit. This experiment is aimed at improving metal production by studying the quality of titanium alloy test pieces and performing mathematical analysis of possible problems arising in the process of its operational testing.

scholarly journals Prediction of Fatigue Limit of Spring Steel Considering Surface Defect Size and Stress Ratio

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 483
Author(s):  
Takehiro Ishii ◽  
Koji Takahashi
Keyword(s):  
Fatigue Limit ◽  
Stress Ratio ◽  
Surface Defects ◽  
High Strength Steels ◽  
High Strength ◽  
Fatigue Tests ◽  
Spring Steel ◽  
Defect Size ◽  
Small Surface ◽  
Stress Ratios

Surface defects decrease the fatigue limit of metals. In this study, the effects of surface defects on the fatigue limit of high-strength spring steel specimens were investigated. Several equations to predict the fatigue limit of specimens with surface defects were evaluated. Specimens with a semicircular slit with depths ranging from 30 to 400 µm were prepared. The Vickers hardness of the specimen was approximately 470 HV. Bending fatigue tests were performed at stress ratios ranging from −2 to 0.4. The fatigue test results showed that the fatigue limit decreased with an increase in the slit depth. Moreover, the maximum defect size that resulted in a decrease in the fatigue limit was dependent on the stress ratio. On comparing the predicted fatigue limits with the experimental results, it was confirmed that the predictions made based on the modified El-Haddad model were in good agreement with the experimentally obtained data. Thus, this model can be used to evaluate the fatigue limit of high-strength steels containing small surface defects with different stress ratios.

TIMETAL 829

Alloy Digest ◽  
2001 ◽  
Vol 50 (8) ◽  
Keyword(s):  
Fracture Toughness ◽  
Titanium Alloy ◽  
High Temperature ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Alloy ◽  
Turbine Engine ◽  
Major Application ◽  
Alpha Titanium ◽  
Engine Components

Abstract TIMETAL 829 is a Ti-5.5Al-3.5Sn-3Zr-1Nb-0.25Mo-0.3Si near-alpha titanium alloy that is weldable and has high strength and is a creep resistant high temperature alloy. The major application is as gas turbine engine components. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness, creep, and fatigue. It also includes information on forming and heat treating. Filing Code: TI-118. Producer or source: Timet.

UNS R54620

Alloy Digest ◽  
1987 ◽  
Vol 36 (7) ◽  
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Time Use ◽  
Temperature Stability ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Stability ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Long Time

Abstract UNS No. R54620 is an alpha-beta titanium alloy. It has an excellent combination of tensile strength, creep strength, toughness and high-temperature stability that makes it suitable for service to 1050 F. It is recommended for use where high strength is required. It has outstanding advantages for long-time use at temperatures to 800 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-86. Producer or source: Titanium alloy mills.

ATI 6-2-4-2

Alloy Digest ◽  
2020 ◽  
Vol 69 (8) ◽  
Keyword(s):  
Tensile Strength ◽  
Titanium Alloy ◽  
High Temperature ◽  
Creep Strength ◽  
High Strength ◽  
Heat Treating ◽  
Good Combination ◽  
Long Term Stability ◽  
Temperature Performance

Abstract ATI 6-2-4-2 is a near-alpha, high strength, titanium alloy that exhibits a good combination of tensile strength, creep strength, toughness, and long-term stability at temperatures up to 425 °C (800 °F). Silicon up to 0.1% frequently is added to improve the creep resistance of the alloy. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ti-169. Producer or Source: ATI.

TIMETAL 685

Alloy Digest ◽  
2007 ◽  
Vol 56 (10) ◽  
Keyword(s):  
Fracture Toughness ◽  
Titanium Alloy ◽  
Shear Strength ◽  
Physical Properties ◽  
Tensile Properties ◽  
Creep Resistance ◽  
Aerospace Industry ◽  
High Strength ◽  
Heat Treating

Abstract Timetal 685 is a titanium alloy with 6 Al, 5 Zr, 0.5 Mo, and 0.25 Si. It is a near-alpha alloy with high strength and creep resistance. Applications are in the aerospace industry. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and shear strength as well as fracture toughness and creep. It also includes information on forming, heat treating, and joining. Filing Code: TI-142. Producer or source: Timet.

Selective Laser Melted Titanium Alloy for Transgingival Components: Influence of Surface Condition on Fibroblast Cell Behavior

2021 ◽  
Author(s):  
Marie‐Joséphine Crenn ◽  
Aurélie Benoit ◽  
Géraldine Rohman ◽  
Thomas Guilbert ◽  
Olivier Fromentin ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Surface Condition ◽  
Fibroblast Cell ◽  
Cell Behavior

scholarly journals Multi-Stage Cold Forging Process for Manufacturing a High-Strength One-Body Input Shaft

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 532
Author(s):  
A Jo ◽  
Myeong Jeong ◽  
Sang Lee ◽  
Young Moon ◽  
Sun Hwang
Keyword(s):  
High Strength ◽  
Microstructural Characterization ◽  
Fatigue Tests ◽  
Machining Process ◽  
Cold Forging ◽  
Element Analysis ◽  
Forging Process ◽  
Input Shaft ◽  
Multi Stage ◽  
The One

A multi-stage cold forging process was developed and complemented with finite element analysis (FEA) to manufacture a high-strength one-body input shaft with a long length body and no separate parts. FEA showed that the one-body input shaft was manufactured without any defects or fractures. Experiments, such as tensile, hardness, torsion, and fatigue tests, and microstructural characterization, were performed to compare the properties of the input shaft produced by the proposed method with those produced using the machining process. The ultimate tensile strength showed a 50% increase and the torque showed a 100 Nm increase, confirming that the input shaft manufactured using the proposed process is superior to that processed using the machining process. Thus, this study provides a proof-of-concept for the design and development of a multi-stage cold forging process to manufacture a one-body input shaft with improved mechanical properties and material recovery rate.

Fatigue and Burst Analysis of Hy-140(T) Steel Pressure Vessels

1970 ◽  
Vol 92 (1) ◽  
pp. 11-16 ◽  
Author(s):  
J. M. Barsom ◽  
S. T. Rolfe
Keyword(s):  
Yield Strength ◽  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
High Strength Steels ◽  
High Strength ◽  
Fatigue Tests ◽  
Pressure Vessels ◽  
High Yield ◽  
Corrosion Properties ◽  
Burst Analysis

Increasing use of high-strength steels in pressure-vessel design has resulted from emphasis on decreasing the weight of pressure vessels for certain applications. To demonstrate the suitability of a 140-ksi yield strength steel for use in unwelded pressure vessels, HY-140(T)—a quenched and tempered 5Ni-Cr-Mo-V steel—was fabricated and subjected to various burst and fatigue tests, as well as to various laboratory tests. In general, results of the investigation indicated very good tensile, Charpy, Nil Ductility Transition Temperature (NDT), low-cycle fatigue, and stress-corrosion properties of HY-140(T) steels, as well as very good burst tests results, in comparison with existing high-yield strength pressure-vessel steels. The results also indicate that the HY-140(T) steel should be an excellent material for its originally designed purpose, Naval hull applications.

Sign in / Sign up

Export Citation Format

Share Document