Conductometry of aluminum with EDTA and NTA as well as oxalic, succinic, and benzoic acids in DMF (dimethyl formamide) has been investigated. Chelatometry with EDTA for the determination of aluminum in aqueous solution was not easy or rapid because Al was present in various types of anion in the solution. In DMF solution, AlCl₃ was present in cations such as [AlCl_3-x⋅DMF]⁺. After a large amount of DMF was added to the solution, conductometric titration of AlCl₃ was made with DMF solution of carboxylic acid derivatives (oxalic, succinic, benzoic acids, NTA, and EDTA), and 3 inflection points were observed for each solute in DMF as follows:
Al: oxalic acid 2:1, 1:1, and 2:3
Al: succinic acid 2:1, 1:1, and 2:3
Al: benzoic acid 1:1, 1:2, and 1:3
Al: NTA 3:1, 2:1, and 1:1
Al: EDTA 4:1, 2:1, and 1:1
However, the inflection points for EDTA 2:1 and 1:1 were considered to be weak, and Al was determined by the point of 4:1.
The determination of aluminum in oxalic acid, phosphoric acid, sulfuric acid and other aluminum surface finishing solutions were rapidly determined by the present method after a large amount (10 times of the sample solution) of DMF was added.

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The effects of Shop Primer on the weldability of high tension steel were investigated. The Shop Primer employed included 3 kinds; i.e., an organic zinc primer and 2 kinds of wash primer, and the thickness of the coated layers was about 10 and 20μ, respectively. Concurrently, the weldability of uncoated high tension steel was also investigated. The arc welding was processed by manual weld in each case.
On each of these specimens, examinations were made for welding workability, bead appearance, X-ray transmission, analysis of zinc content in the deposited metal, X-ray diffraction of coated bead slag, and macro- and micro-structure and static mechanical strength of the weld zone.
The results were as follows:
(1) Organic zinc primer or wash primer could satisfactory be used for priming coat, when the welding was processed under the following proper conditions.
a) The steel plate was properly beveled.
b) The spacing between included angles was considerable.
c) The arc length was properly maintained.
(2) It seems that organic zinc primer had the most excellent weldability among various types of Shop Primer with respect to rust preventive and corrosion resistant properties. Accordingly, it was concluded to be an effective Shop Primer.

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The plating conditions of titanium carbide on iron were investigated in the temperature range of 850-1100°C. Hydrocarbon mixed with titanium tetrachloride carried by hydrogen was introduced over a test specimen of cast iron or mild steel. The direct coating on iron resulted in severe corrosion and cementation of the ground metal, which disturbed the adherence of carbide layer. However, preliminary electroplating of cobalt on the iron was found to be effective for preventing the corrosion and cementation.
Titanium carbide layer was obtained above 900°C only, and its growth rate showed a maximum at 950-1000°C. The increase in the thickness of the carbide layer formed was determined to be proportional to the plating time by the curve representing the weight increase.
The layer was apt to be deposited at the position near the gas inlet above 950°C. The growth rate attained to 1.9μ/min. at 950°C in case of the flow rates of hydrogen and propane were 7 and 0.32cc/s., respectively The availability of the constituent carbon in various hydrocarbons was arranged in the decreasing order as folllows:
i-C₅H₁₂>C₂H₆>C₃H₈>C₃H₆>C₂H₄>CO>CH₄

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The mechanism of adhesion between coated film and substrate (base metal) processed by electro-plating, hot dipping, flame spray coating, vapor plating, etc. was semi-quantitatively observed by means of X-ray microanalyzer. The results obtained within the analyzing limit of the microanalyzer were as follows:
(1) Each adhesion of electroplated Ni or Cr film on Fe substrate and electroplated Cr film on Ni substrate was considered to be simple mechanical bonding.
(2) Each adhesion of hot dipped film on Cu or Fe substrate and hot dipped Zn film on Fe substrate was found to be the bonding by mutual diffusion, because deep diffusion layer was observed. Furthermore, it was found in soldering that diffusing power of Sn in soft solder was more effective than that of Pb.
(3) In regard to metallikons, adhesion of flame-coated Zn or Cu film on Fe substrate was mechanical bonding; however, in Mo metallikon, slight diffusion bonding was observed between the substrate and coated film.
(4) In plasma-flamed WC film on the plasma-flamed undercoating of Al (20%) and Ni (80%) covering Fe substrate (steel plate) was found that Ni partly diffused into both substrate and WC film, but some of Ni was alloyed which strengthened the adhesion of the both films.
(5) In vapor plated TiC layer on steel plate processed by thermal decomposition of mixed vapor of TiCl₄ and toluene at 1200°C, the boundary layer between substrate and coated TiC was completely alloyed and the thickness of alloyed layer was considerably large which permitted the presence of pure TiC layer only near the surface.

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