EVALUATION OF TWO TITANIUM FORGING ALLOYS

reportActive / Technical Report | Accession Number: AD0662700 | Open PDF

Abstract:

Ti-6Al-6V-2Sn and Ti-13V-11Cr-3Al both solution heat-treated and aged were evaluated. Both small-size specimens and full-size helicopter components were tested. Small-size specimens were tested for resistance to fatigue crack initiation, resistance to fatigue crack propagation, and fracture toughness. Fatigue crack initiation tests included tension-tension tests both of unnotched specimens and of joints. Helicopter main rotor cuffs were evaluated in fatigue crack initiation and fatigue crack propagation tests with expanded holes and with reamed holes. The titanium alloy cuff test results were compared to those for Ti-6Al-4V annealed and 4340 steel heat-treated to a 125-ksi minimum ultimate tensile strength cuffs and to small-size specimen tests. Tensile test data, chemical analysis and forging parameters are also presented. The crack initiation resistance of Ti-6Al-6V-2Sn was found to be superior to that of Ti-13V-11Cr-3Al. Axial tension-tension fatigue results showed 50 higher fatigue strengths for Ti-6Al-6V-2Sn than for Ti-13V-11Cr-3Al. Joint fatigue tests also showed higher strength values for the Ti-6Al6V-2Sn alloy. Fracture toughness results were comparable for both alloys. Joint fatigue test evaluations were made for reamed, shot peened, and expanded holes. The highest fatigue strength values were associated with specimens having expanded holes. The Ti-6Al-6V-2Sn cuffs with both reamed and expanded cuff-to- spar attachment holes showed higher fatigue crack initiation strength values than those of the Ti-13V-11Cr-3Al.

Author(s):
Matusovich, Charles J.
Author Organization(s):
UNITED TECHNOLOGIES CORP STRATFORD CT SIKORSKY AIRCRAFT DIV
Descriptive Note:
Final rept.
Supplementary Note:
DOI: 10.21236/AD0662700
Pagination:
0090

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
SER-50430, USAAVLABS-TR-67-43
Contract/Grant Number(s):
DA-44-177-AMC-256(T)
Task Number(s):
1F121401A14176
Monitor Series:
TR-67-43, USAAVLABS
 Subject Terms
Joint Capability Areas:
JCA_1_Force Support; JCA_1.2_Force Preparation; JCA_5_Command and Control; JCA_5.3_Planning; JCA_5.5.2_Task; JCA_5.5_Direct; JCA_6.4.1_Secure Information Exchange
Communities of Interest:
Air Platforms
Descriptor(s):
*FORGING, *TITANIUM ALLOYS, ALUMINUM ALLOYS, CHROMIUM ALLOYS, CRACK PROPAGATION, FATIGUE(MECHANICS), FRACTURE(MECHANICS), TENSILE PROPERTIES, TIN ALLOYS, TOUGHNESS, VANADIUM ALLOYS
Field(s)/Group(s):
Metallurgy and Metallography, Fabrication Metallurgy
Keyword(s):
TITANIUM ALLOY 3AL 11CR 13V, TITANIUM ALLOY 6AL 2SN 6V
Report Date:
1967 Aug 01