Titanium Alloy Composition for Near-Net Shape Casting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high material and processing costs of titanium alloys, particularly due to the need for tightly controlled minor elements like iron and oxygen, and the costly machining processes, limit their widespread application in industries such as aerospace, defense, and energy, despite their potential for low-weight, corrosion-resistant structures.
Innovation Solution
A titanium alloy composition with specific weight percentages of aluminum, vanadium, molybdenum, chromium, iron, oxygen, and incidental elements, processed using near-net shape casting and cooling methods that avoid hot working, enabling the use of lower-quality scrap materials and reducing manufacturing costs while achieving a basketweave microstructure for enhanced strength and ductility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If titanium alloys are produced with tightly controlled minor elements (ELI grade), then mechanical property uniformity is improved, but material cost increases
Solution Approach 1:
The patent changes the compositional parameters by allowing higher ranges of minor elements (Fe: 0.05-0.60%, O: 0.05-0.35%) compared to conventional ELI grades, while compensating with optimized major alloying elements (Al: 3.0-6.0%, V: 2.0-4.0%, Mo: 0.5-4.5%, Cr: 1.0-2.5%) to maintain mechanical properties without requiring ultra-low interstitial control
Solution Approach 2:
The patent creates a composite alloy system combining Ti-6Al-4V base composition with additional Mo and Cr elements, where the synergistic interaction of multiple alloying elements compensates for the relaxed control of minor elements, achieving cost reduction while maintaining performance
2Strength
If titanium alloys are produced by conventional working processes, then mechanical properties are improved, but processing cost and material waste increase
Solution Approach 1:
The patent performs preliminary alloy design with optimized composition ranges that enable direct casting to near-net shapes without requiring subsequent hot working or extensive machining, preparing the material in advance with the right properties for final application
Solution Approach 2:
The patent adopts a casting process that reduces or eliminates costly hot working and machining operations, accepting that some material may be used as-is or with minimal processing rather than investing in expensive multi-step forming and machining sequences
3Strength
If titanium alloys are produced by conventional working processes, then mechanical properties are improved, but material waste increases
Solution Approach 1:
The alloy composition is preliminarily optimized to enable near-net shape casting, reducing the need for subsequent machining operations that would remove material, thereby minimizing waste while maintaining mechanical properties
Solution Approach 2:
The patent replaces conventional mechanical working processes (forging, rolling, machining) with a casting process that directly produces near-net shapes, eliminating or reducing material removal operations and associated waste
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution results in titanium alloys with a combination of high strength and toughness at lower costs, using low-cost raw materials and processing methods that tolerate incidental elements, reducing material waste and machining costs, and achieving superior mechanical properties compared to conventional titanium alloys.
Implementation Method 1
cooling the alloy with a gas pressurized to about 2 atm
Data Source
AI summary
Provided herein are titanium alloys that can achieve a combination of high strength and high toughness or elongation, and a method to produce the alloys. By tolerating iron, oxygen, and other incidental elements and impurities, the alloys enable the use of lower quality scrap as raw materials. The alloys are castable and can form α-phase laths in a basketweave morphology by a commercially feasible heat treatment that does not require hot-working or rapid cooling rates. The alloys comprise, by weight, about 3.0% to about 6.0% aluminum, 0% to about 1.5% tin, about 2.0% to about 4.0% vanadium, about 0.5% to about 4.5% molybdenum, about 1.0% to about 2.5% chromium, about 0.20% to about 0.55% iron, 0% to about 0.35% oxygen, 0% to about 0.007% boron, and 0% to about 0.60% other incidental elements and impurities, the balance of weight percent comprising titanium. There exists an unmet need to produce titanium alloys for use in aerospace applications which have a refined equiaxed grain structure. This can be beneficial for fatigue critical applications. The technology developed by QuesTek describes a titanium alloy and manufacturing methods thereof to obtain equiaxed grains on the order of 300 microns and corresponding UTS of approximately 170 ksi. In addition, various forms of the alloys are disclosed including ingots, billets, powders and wire in accord with the described microstructure and physical characteristics.