MACHINING OF REFRACTORY MATERIALS. Phase II Technical Engineering Report, February 1, 1962 to April 30, 1962

Technical Report · Tue May 01 04:00:00 EDT 1962

OSTI ID:4828513

Nowikowski, L J; Zlatin, N; Field, M

Machining studies were performed on pressed and sintered unalloyed tungsten, D-31 niobium alloy, 90Ta10W alloy, molybdenum TZM and Mo-0.5% Ti alloys, and a high temperature glass ceramic material. The investigation consisted of drilling and grinding tests on tungsten; turning, face milling, and grinding on D-31 niobium, turning, drilling, reaming, and tapping on 90Ta-10W alloy,; face milling, end milling, drilling, reaming, tapping, and grinding on molybdenum alloys; and grinding of the high temperature glass ceramic. A drill life of 27 holes was obtained on tungsten heated to 800 deg F using a 0.213 in. dia. solid carbide drill at 200 ft/min. In grinding, a G Ratio of 5.2 was obtained with a 32A46N5VBE wheel. In turning D-31 niobium, a tool life of 35 minutes was obtained at 300 ft/min. with a C-2 (K6) carbide, and a cutter life of 100 m-. of work travel in face milling with an M-2 HSS cutter at 98 ft/min. The best G Ratio, 7.5 for grinding D-31 was obtained with a 32A46K8VBE wheel using a KNO/sub 2/ solution grinding fluid. The 90Ta-10W alloy was somewhat more difficult to machine. Tool life in turning with a C-2 (K6) carbide was 25 min at 100 ft/min. In drilling, 45 holes were obtained with a 0.193 in. dia. M-1 HSS drill at 50 ft/min. Reaming with a 0.213 in. dia. M-2 HSS reamer at 85 ft/min gave 68 holes, and a tap life of 60 holes was obtained at 4 ft/min with a 1/4-28 M-10 HSS tap. In milling TZM molybdenum with a C-2 (883) carbide face mill at 350 ft/min a cutter life of 110 in. of work travel was obtained. A T-15 HSS end mill produced 80 in. of work travel at 190 ft/min. Drilling with a 0.250 in. dia. M-1 HSS drill produced 100 holes at 125 ft/min and reaming with a 0.272 in. dia. M-2 HSS reamer gave a tool life of 50 holes at 60 ft/min. Tapping with a 5/16-24 M-10 HSS tap at 70 ft/min produced 100 holes. Grinding ratios of 15 to 25 were obtained using aluminum oxide wheels with KNO/sub 2/ solution as a grinding fiuid. Silicon carbide wheels gave the best G Ratios, 30 to 40, in grinding a high temperature glass ceramic. Wheel speeds of 5000 to 6000 ft/mth and a down feed of 0.002 in./pass produced the best G Ratio. (auth)

• Research Organization: Metcut Research Associates Inc., Cincinnati
• NSA Number: NSA-16-020990
• OSTI ID: 4828513
• Report Number(s): ASD-TR-7-532a(VI)
• Country of Publication: United States
• Language: English

Related Subjects

ALLOY-TZM
ALUMINUM OXIDES
CARBIDES
CERAMICS
GLASS
HIGH TEMPERATURE
LUBRICATION
MACHINING
METALS, CERAMICS, AND OTHER MATERIALS
MOLYBDENUM ALLOYS
NIOBIUM ALLOYS
NITRITES
PERFORMANCE
POTASSIUM COMPOUNDS
REFRACTORIES
SILICON CARBIDES
TANTALUM ALLOYS
TESTING
TITANIUM ALLOYS
TOOLS
TUNGSTEN
TUNGSTEN ALLOYS
VELOCITY