節(jié)選自Metallurgical Exmination of Soviet 45mm, 57mm, and 85mm APHE Projectiles; ADA443218; 1952-08-06

The 45MM and 57MM shot were uniformly heat treated to a hardness of approximately Rockwell C 50-55 while the 85MM shot was decrementally hardened from Rockwell C 46-50 at the nose to ?Rockwell C 25 at the base.?

45 mm和57 mm均勻熱處理，整體硬度50~55 HRC。85 mm硬度自頭部的46~50 HRC降低至尾部的25 HRC

The carbon contents of the subject Soviet shot are in the range of 0.32 - 0.38% as compared to 0.50 - 0.60% carbon employed in domestic shot steels. The result of the lower carbon content is to lower the maximum hardness of the shot to the range of Rockwell C 50-55 as compared to Rockwell C 60 for American shot.?

蘇聯(lián)穿甲彈用鋼含碳量在0.32~0.38%之間，而國內(nèi)通常為0.5~0.6%。更高的含碳量意味著更高的硬度，國產(chǎn)穿甲彈的硬度通常約為60 HRC

The bodies of all three shot were made from medium carbon, manganese-silicon-chromium steels of very similar compositions, see Table I. Although the evidence provided by the subject three shot is, of course, extremely limited, there seems to be no indicationof selection of alloy content consistent with hardenability equirements to harden through sections of varying size. As a matter of fact, the largest shot, the 85MM APHE, has the lowest carbon and total alloy content. In domestic practice, it is usual to employ higher alloy steels for shot of larger caliber in order to obtain full hardening of the heavier sections. The low carbon content of the subject shot is noteworthy. In American practice, it is common to employ alloy steels having carbon. contents of 0.50-0.60% in order to harden the shot to Rockwell C 60 upon quenching. Steels with 0. 32-0.38% carbon harden to Rockwell C 52-55 upon complete transformation to martensite.

彈體材料均為中碳錳硅鉻鋼，成分相近，見下表。沒有證據(jù)表明蘇聯(lián)會(huì)根據(jù)尺寸調(diào)整合金成分。口徑最大的85 mm碳和合金含量最低。國內(nèi)通常的做法是在增大口徑同時(shí)提高合金含量以確保大截面能完全硬化。(譯注：作為示例，Armox 500和Mars 600均隨板厚增大相應(yīng)地調(diào)整成分)

Manganese - silicon- chromium steels containing approximately 1.5% silicon have been widely observed in Soviet ordnance materiel, being used in gun components, armor, and armor-piercing shot. The low molybdenum content indicates that this element is present only as a residual rather than as an alloying element. Molybdenum is very widely employed in this country in ordnance materiel to minimize or avoid temper embrittlement, being used in quantities in the range of 0.20 to 0.60%. Since this element is almost a specific for avoidance of embrittlement, its absence in Soviet ordnance materiel may safely be taken as an indication of its strategic nature in the Soviet metal supply.

硅含量1.5%的錳硅鉻鋼廣泛用于蘇聯(lián)火炮、裝甲和穿甲彈。鉬含量很低，表明僅是雜質(zhì)而非合金元素。鉬廣泛用于國產(chǎn)軍用鋼，以抑制回火脆化，含量通常在0.2~0.6%。(譯注：最典型的RHA 4340/40CrNiMo(A))

The hardness patterns of the subject shot are radically different from those of domestic shot. In American practice, shot are heat treated to the maximum hardness obtainable (Rockwell C 60 and higher) and then differentially tempered to have hardnesses of approximately Rockwell C 59 at the bour relet and gradually dropping to Rockwell C 45 at the base. It has been found that lowering the hardness of shot noses below Rockwell C 60 results in more extensive shatter of the shot against armor, as well as a reduction in the velocity of impact at which hatter initiates.

美國穿甲彈的頭部硬度通常高于60 HRC，倒角處降低至59 HRC，尾部45 HRC。頭部硬度低于60 HRC會(huì)導(dǎo)致彈體受破壞靶板破壞過強(qiáng)。

The reduced hardness of the 45MM and 57MM shot is understandable, since an effort was obviously made to increase the toughness of these shot since the blunt nose shape of these shot make shatter almost inevitable against heavy armor targets and at high terminal velocities. In the case of the 85MM shot, however, the low overall hardness should detract from the penetration performance of this ogival nosed shot.

45 mm和57 mm的低硬度是為了提高韌性，因?yàn)殁g頭彈在高速打擊重裝甲是幾乎必然發(fā)生破壞。對(duì)于尖頭的85 mm，降低硬度應(yīng)該會(huì)劣化穿甲能力。