在讨论铅酸蓄电池工业用板栅合金之前，必须详细讨论合金的相图。铅锑合金中，锑含量不同，合金的凝固点（温度）不同，若测出铅锑合金中一系列不同锑含量的凝固点（温度）作纵坐标，合金中锑含量为横坐标作图，为了研究相图方便，把合金液（熔融体）固（凝固体）体系中，物理与化学性质以及组成都均匀一致的部分称为“相”，比如液相、固相。相图是指各种组成的合金随温度变化时其状态变化的图解。在铅锑合金相图中，a称为a固溶体。a固溶体中铅多锑少，即铅中熔有少量锑。p 称为日固溶体，日固溶体中锑多铅少，即锑中熔有少量铅。从铅锑合金相图中看到，当锑含量13 ％时，铅锑合金的凝固点最低。含锑少于13 纬时，合金从L （液相）温度降至凝固点时，首先出现a 固溶体，温度继续下降至C/E/D 区域合金又出现a 相与p 相。
在生产实践中，板栅需要细小均匀的晶体。铸板栅时要保持一定冷却速度才能得到极细小晶体粒，。固溶体内含锑量随温度降低而减少，开始时锑含量有2 .5 % ，继续冷却至含锑量约为0.4 ％的温度，若冷却速度过快，Q 固溶体来不及变化就已经成了固相，这时。固溶体是不稳定的，部分锑以p 固溶体形式在固熔体中析出，同时由于在固相中扩散困难，造成。固溶体与p 固溶体分布不均匀，板栅因之发脆。另在板耳处（或粗筋处）因合金液量多，冷却就相对要慢，也容易造成局部锑含量过多，出现“白斑”甚至裂纹。
合金中锑含量降低，出现“热裂”的趋势就越大，因此生产的板栅比较脆。这是由于凝固成粗晶粒结构，并含有热裂纹，并沿着晶粒的边界分布。低锑合金的热裂现象是可以避免的，通常添加变晶剂（成核剂）就能消除。
BE discussing before sour industry of lead uses plank grid metal alloy, have to discuss metal alloy mutually in detail diagram.In the metal alloy of lead Ti, the Ti content is different, the freezing point(temperature) dissimilarity of metal alloy, if the freezing point(temperature) that tests to find out a series of and different Ti content in the metal alloy of lead Ti makes Zong to sit a mark, in the metal alloy Ti content for horizontal make diagram by mark, for the sake of research mutually diagram convenience, chase metal alloy liquid(meltdown body) solid(solidify body) system in, physics and chemistry property and constitute all even consistent of part be called "mutually", for example liquid mutually, solid phase.Mutually the diagram means that various metal alloy for constituting changes with the temperature its status change of illustrated manual table.In the metal alloy of lead Ti mutually in the diagram, the an is called a solid dissolve a body.The an is solid to dissolve many Tis of lead in bodies little, namely the Rong in lead has a little amount Ti.The p is called a day solid dissolve a body, the day is solid to dissolve many leads of Ti in bodies little, namely the Rong in Ti has a little amount lead.See from the metal alloy of lead Ti mutually the diagram, be a Ti content 13%, the freezing point of the metal alloy of lead Ti is lowest.When metal alloy declined from L(the liquid is mutually) temperature to freezing point while containing less than 13 latitudes of Tis, appear a first solid dissolve a body, the temperature continues to descend to C|E|D district metal alloy again appear a mutually and the p was mutually.
In the middle of producing and practicing, the plank grid needs small and even crystal.Zhu plank grid would not° until keep certain cooling speed get the smallest crystal grain, .Is solid to dissolve a body to contain the amount of Ti lowers but reduces with the temperature, the Ti content contains 2.5%s while starting and continue cooling to contain the amount of Ti as about 0.4% temperatures, if cool off speed to lead quickly, the Q is solid to dissolve a body too late variety have already become a solid phase, at this time.It is unsteady to is solid to dissolve a body, parts of Tis dissolve a figure type by solid p the Xi is in the solid Rong body and result in due to spreading a difficulty in the solid phase at the same time.Is solid to dissolve body and p solid dissolve a body to distribute asymmetry, because of does the plank grid deliver frailty.Is another the place(or thick Jin place) is at the plank ear because metal alloy liquid the quantity is many, cool off opposite have to be slow, also easily make partial Ti content excessive, appear "white spot" the crack is even.
The Ti content lowers in the metal alloy and appear the trend of "is hot to split" more big, consequently production of plank grid comparison frailty.This is in order to solidifying thick crystal grain structure, and imply hot crack, and along the boundary of crystal grain distributes.The hot crack phenomenon of low Ti metal alloy can avoid, usually add to become a crystal and then can get rid of.
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