ALUMINUM ALLOY SUBSTRATE FOR MAGNETIC DISK AND MANUFACTURING METHOD THEREFOR, AND MAGNETIC DISK USING THE ALUMINUM ALLOY SUBSTRATE FOR MAGNETIC DISK

• Main Authors: HATAKEYAMA HIDEYUKI, YONEMITSU MAKOTO, KITAWAKI KOTARO, SAKAMOTO RYO, OTA YUKI
• Format: Patent
• Language: English; Japanese
• Published: 16.01.2020
• Subjects: ALLOYS; CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS ANDNON-FERROUS ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; METALLURGY; PHYSICS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

To provide an aluminum alloy substrate for a magnetic disk having good flattering property and strength, a manufacturing method therefor, and a magnetic disk using the aluminum alloy substrate for a magnetic disk.SOLUTION: There are provided an aluminum alloy substrate for a magnetic disk consisting of an aluminum alloy containing Fe:0.05 to 3.00 mass%, Zr:0.01 to 0.50 mass% and the balance Al with inevitable impurities, in which distribution density of an Al-Zr-based intermetallic compound having the longest diameter of 1 μm or more of 1/mmor less, a manufacturing method therefor, and a magnetic disk having an electroless Ni-P plating treatment layer and a magnetic substance layer thereon on a surface of the aluminum alloy substrate for a magnetic disk.SELECTED DRAWING: Figure 1 【課題】良好なフラッタリング特性と強度を有する磁気ディスク用アルミニウム合金基板及びその製造方法、ならびに、この磁気ディスク用アルミニウム合金基板を用いた磁気ディスクを提供する。【解決手段】Ｆｅ：０．０５〜３．００ｍａｓｓ％、Ｚｒ：０．０１〜０．５０ｍａｓｓ％を含有し、残部Ａｌ及び不可避不純物からなるアルミニウム合金からなり、１μｍ以上の最長径を有するＡｌ−Ｚｒ系金属間化合物の分布密度が１個／ｍｍ２以下であることを特徴とする磁気ディスク用アルミニウム合金基板及びその製造方法、ならびに、当該磁気ディスク用アルミニウム合金基板の表面に、無電解Ｎｉ−Ｐめっき処理層とその上の磁性体層が設けられている磁気ディスク。【選択図】図１