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OCR for page 197
Appendix H TITANIUM SPONGE SPECIFICATIONS The following material is an excerpt from U. S. National Stockpile Purchase specification P-97-~7 June 2, 1982 (supersedes P-97-R6, October l9, 1977~: This specification covers titanium metal sponge in the form and quality satisfactory for stockpiling and intended industrial uses. COMICAL AND PHYSICAL REQUIREMENTS Each lot of titanium purchased under this specification shall be uniform in appearance and thoroughly blended . It shall be free of inclusions, oxides, nitrides, and other contaminants , and shall have a uniform matte gray color. Deviations from this color, such as bluish or yell owish hues, may indicate the Dresence of excessive amounts of impurities and the need for micro-samples to be taken for chemical analysis. The material purchased shall conf arm to the following applicable chemical and physical requirements: A. Chemical Requirements: Element Percent by Weight (dry Basisja - Grade lA~Ou Grade lB-O v - Type A l Type A Type B Type C Nitrogen Max. 0.010 OeO15 OeO15 OeO08 Carbon Max. 0.020 0.025 0.020 0.020 Sodium (total) Max. - - 0.19 0.01 Magnesium Max. 0.08 0.50 0.08 Lithium Max. - - - 0.09 Potas slum Max . Al''minum Max. - O.07 Chlorine Max. O . 10 0.20 0.20 0.10 197

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198 Chemical Requirements (continued ): E1 event - Percent by Weight (Dry Basis)a Grade 1A - b Grade lB-h Type A Type B Type C Type A Iron Max. 0.08 0.10 0.04 0.04 Silicon Max . O . 04 0 . 04 0 .04 0 .04 Hydrogen Max. 0.005 O. 03 0.05 0.02 Oxygen Max. 0.10 0.10 0.10 0.07 Water Max. 0.02 0.02 0.02 0.02 All other elements (total) Max. 0.05 0.05 0.05 0.05 Titanium (nominally) Min. 99.6 99.1 99.3 99 .6 a The sample shall be dried f or 2 hours at 135C. b Type A Magnesium reduced and finished by vacuum distillation. Type B Magnesium reduced and finished by acid leaching or inert gas sweep distillation. Type C Sodium reduced and finished by acid leaching. B. Physical Requirements: Hardness (BHN): The maximum Brinell hardness of each lot of Type A and Type D titanium shall be 100, and each lot of Type B and Type C titanium shall be 120. The Brinell hardness of a lot shall be the average of the hardness determinations made on button representing the lot of titanium. However, no batch having a Brinell hardness more than 10 points above the maximum allowable for the lot shall be used in blending for that lot . The method of measurement shall be in accordance wi th ASTM Method E10, Test for Brinell Hardness of Metallic Materials, using a lO~m ball, 1500-kg f load in the 100 to 200 Bhn range and a 500-kg f load in the under 95 Bhn range and a 30-s dwell. No te: P-9 7-R7 also contains Section III on Packaging, Marking, Identif ication, Shipping and Handling .

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199 The following material is an excerpt from ASTM B-299-74: (ASTM B-29 9-80 is in preparation) STANDARD SPECIFICATION FOR TITANIUM SPONGE This specification covers virgin titanium metal melting stock. This virgin metal is commonly designated as sponge titanium because of its porous, spongelike texture. Manufacture Sponge titanium is usually prepared by reduction of titanium tetrachloride and gets its spongelike character from the processes involved in production. This spongy characteristic, however; is not considered essential and may be expected to vary greatly with manufacturing methods. The metal is usually supplied in lumps of 1/2 inch (12.7 mm) or less in size. This specification, however, is not limited to metal prepared by reduction of the tetrachloride or to material of the size indicated. Only virgin titanium, free of scrap and intentionally added contaminants, shall be supplied under this specif ication. It shall be supplied in uniform, well-mixed blends , each of which shall be clearly designated. Sampling The sampling method used shall be a matter of agreement between the manufacturer and the purchaser. The following are acceptable industrial practices: The sample for determining the conformance of the lot to the chemical and physical requirements shall be obtained by sampling to produce a O. 50 percent s ample but not less than 30 lb (14 kg) . The blended evaluation sample shall be compacted into consumable electrodes f or melting . A portion of the compact shall be sawed off prior to melting and sampled by drilling for the analysis of magnesium, sodium, chlorine, and hydrogen. The electrode shall be melted under an inert atmosphere in a vacuum to form an ingot. The resulting ingot shall be sampled by sawing a transverse section approximately 1/2 inch (12.7 mm) thick from the center of the ingot. After machining both sides of this slab, five analyses and f ive hardness readings are to be made at locations equal distances apart and diagonally across the machined surfaces. Slices 1/4 inch (6.35 mm) wide are to be taken from this slab, parallel to the hardness locations, and sheared to obtain samples weighing approximately 0.1 g. for oxygen and nitrogen analysis. One half of the slab shall accompany the shipment and the other half shall be retained by the manufacturer.

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200 Chemical Requirements The titanium metal supplied under this specification shall conform to the chemical composition requirements prescribed in the Table below. Element Weight perk_ MW120 ML-120 SL-12 0 GP-1 Nitrogen, max 0.015 0.015 0.015 0.020 Carbon, max 0.020 0.025 0.020 0.025 Sodium, max ~ total) - - 0.19 Magnesium, max 0.05 O.SO Chlorine, max 0. 12 0 . 20 0 .20 0 .20 Iron, max 0.12 0.15 0.05 0.25 Silicon, max 0.04 0.04 0.04 0.04 Hydrogen, max 0.010 0.03 0.05 0.03 Oxygen, max 0.10 0.10 0.10 0.15 All other impuri ties (total), max 0.05 0.05 0.05 0.05 Titanium, balance "nominal) 99.3 99.1 99.3 MD-120 Magnestum-reduced and finished by distillation. ML-120 Magnesium-reduced and finished by leaching or inert gas sweep. SL-120 Sodium-reduced and finished by leaching. Sodium or magnesium, max: 0.50 percent. GP-1A general purpose grade, either magnesium, or sod~um-reduced and finished by leaching or inert gas sweep or both. Methods of Chemical Analysis The methods of analysis shall be in accordance with ASTM Methods E 120, Chemical Analysis of Titanium and Titanium Alloys, or as agreed upon by the manufacturer and the purchaser. Hardness The Brinell hardness of a lot shall be the average of the hardness determinations made on the solid samples prepared as described in Section 4 and the hardness value shall not exceed 120 HB. The method of measurement shall be in accordance with ASTM Method E10 Test for Brinell Hardness of Metallic Materials using a 10-mm ball, 1500-kgf load, and a 30-s dwell.