Advanced Metalworking Solutions for
Naval Systems that Go in Harm's Way

Improved Affordability of Titanium Parts for Marine Corps XM777 Lightweight 155MM Howitzer


Identify, assess, and select lower cost, robust manufacturing approaches as an alternative to the machining/welding assembly.  Develop and demonstrate the alternative manufacturing processes on selected components, and deliver them for testing and implementation.


The XM777 design incorporates a significant amount of Ti-6Al-4V titanium alloy. Currently, all of the major structures are manufactured from titanium plate-work welded together. This is a very expensive approach because of the amount of machining on individual plate-work prior to welding, the setup time and special fixtures required for welding of titanium, and the cost of rework from shrinkage, distortion and contamination. Therefore, alternative manufacturing processes suitable for production of various titanium components are required to reduce cost and eliminate technical problems in order to meet the program schedule. In this project, alternative manufacturing processes will be fully investigated to address the cost and technical issues.

Technical Approach

A two-phase project approach is being employed.

  • In Phase I, Manufacturing Studies of XM777 Components, the best manufacturing practices for selected components will be considered and analyzed.
  • In Phase II, Low Cost Manufacturing Demonstration of Selected XM777 Components, demonstration components will be developed and tested from those components that offer the greatest economical benefit to the XM777 weapon system.


- Overcome technical problems associated with weld shrinkage, product variability, and dimensional instability
- Cost reduction through part reduction, less labor intensive, more efficient manufacturing, and improved quality through substantial reduction in variability and re-work
- Impact on production schedule through improved manufacturing efficiency
- Results are expected to also benefit other weapon systems that may utilize structural titanium (e.g., Future Combat Systems) for lowering weight while improving performance


The completion of the LW155 Howitzer project comes with marked success, including a cost savings of $27 million for the single-piece investment cast spades, qualification of low-cost input materials that will further increase cost reduction, 68% cost savings for the flowformed tube as opposed to baseline production methods and a 44% total weight reduction for the LW155 Howitzer.  The expansion of the vendor network has enhanced the supply redundancy for the program and will see a cost avoidance of $13 million over the full-rate production contract.




James Shields